Relax thread stack size requirements

13 files changed, 2023 insertions, 26 deletions

diff --git a/libpkgconf/buildfile b/libpkgconf/buildfile
index c344ec7..a2f9427 100644
--- a/libpkgconf/buildfile
+++ b/libpkgconf/buildfile
@@ -16,6 +16,9 @@ else
 #
 h{version}: in{version} $src_root/file{manifest}
 
+tclass = $c.target.class
+tsys   = $c.target.system
+
 # Define the PKG_DEFAULT_PATH, SYSTEM_INCLUDEDIR and SYSTEM_LIBDIR macros.
 # The whole idea feels utterly broken (hello cross-compilation) so we will
 # just do bare minimum and wait and see.
@@ -23,7 +26,7 @@ h{version}: in{version} $src_root/file{manifest}
 # @@ We should probably allow to configure these macros via configuration
 #    variables config.pkgconfig.pkg_default_path and alike.
 #
-if ($c.target.class == "windows")
+if ($tclass == "windows")
 {
   inc_dirs = ""
   lib_dirs = ""
@@ -55,17 +58,17 @@ c.poptions += -DPKG_DEFAULT_PATH=\"$def_dirs\" \
 
 # Disable warnings.
 #
-if ($c.target.system == "win32-msvc")
+if ($tsys == "win32-msvc")
   c.coptions += /wd4996 /wd4267
 
-if ($c.target.class == "windows")
+if ($tclass == "windows")
 {
   # See libpkgconf/libpkgconf-api.h for details.
   #
   objs{*}: c.poptions += -DLIBPKGCONF_EXPORT
   obja{*}: c.poptions += -DPKGCONFIG_IS_STATIC
 
-  if ($c.target.system == "mingw32")
+  if ($tsys == "mingw32")
     c.libs += -ladvapi32
   else
     c.libs += advapi32.lib
@@ -81,8 +84,26 @@ liba{pkgconf}: cc.export.poptions += -DPKGCONFIG_IS_STATIC
 # -std=c9x option (is implied by c.std=99 in root.build) and define _GNU_SOURCE
 # for the source files that require such deviations.
 #
-if ($c.target.class != "windows")
+# We will also re-enable definitions of POSIX macros (specifically PATH_MAX)
+# that are disabled by -std=c9x.
+#
+if ($tclass != "windows")
+{
+  # On FreeBSD and MacOS -D_POSIX_C_SOURCE disables declarations of strndup(),
+  # strlcpy() and alike, that are not POSIX. Not very consistent given that
+  # they are also not C99. Luckily, -std=c9x doesn't disable PATH_MAX on these
+  # OSes, so we just don't define the macro for them.
+  #
+  # @@ It all becomes a bit hairy. Should we just undefine the corresponding
+  #    HAVE_* macros in config.h, so the custom function implementations are
+  #    picked up? Alternatively, can we stop specifying the C standard and
+  #    defining _POSIX_C_SOURCE macro altogether?
+  #
+  if ($tclass != "bsd" && $tclass != "macos")
+    c.poptions += -D_POSIX_C_SOURCE=200112L
+
   obj{client fragment path pkg queue tuple}: c.poptions += -D_GNU_SOURCE
+}
 
 # Install into the pkgconf/libpkgconf/ subdirectory of, say, /usr/include/.
 # Also make sure Cflags is properly set in .pc files to pkgconfig/.
diff --git a/libpkgconf/dependency.c b/libpkgconf/dependency.c
index 3078102..6f72dbb 100644
--- a/libpkgconf/dependency.c
+++ b/libpkgconf/dependency.c
@@ -56,7 +56,7 @@ static inline pkgconf_dependency_t *
 pkgconf_dependency_addraw(const pkgconf_client_t *client, pkgconf_list_t *list, const char *package, size_t package_sz, const char *version, size_t version_sz, pkgconf_pkg_comparator_t compare)
 {
 	pkgconf_dependency_t *dep;
-	char depbuf[PKGCONF_BUFSIZE];
+	char depbuf[PKGCONF_SBUFSIZE];
 
 	dep = calloc(sizeof(pkgconf_dependency_t), 1);
 	dep->package = pkgconf_strndup(package, package_sz);
@@ -161,7 +161,7 @@ pkgconf_dependency_parse_str(const pkgconf_client_t *client, pkgconf_list_t *dep
 {
 	parse_state_t state = OUTSIDE_MODULE;
 	pkgconf_pkg_comparator_t compare = PKGCONF_CMP_ANY;
-	char cmpname[PKGCONF_BUFSIZE];
+	char cmpname[PKGCONF_SBUFSIZE];
 	char buf[PKGCONF_BUFSIZE];
 	size_t package_sz = 0, version_sz = 0;
 	char *start = buf;
diff --git a/libpkgconf/dependency.c.orig b/libpkgconf/dependency.c.orig
new file mode 100644
index 0000000..3078102
--- /dev/null
+++ b/libpkgconf/dependency.c.orig
@@ -0,0 +1,309 @@
+/*
+ * dependency.c
+ * dependency parsing and management
+ *
+ * Copyright (c) 2011, 2012, 2013 pkgconf authors (see AUTHORS).
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * This software is provided 'as is' and without any warranty, express or
+ * implied.  In no event shall the authors be liable for any damages arising
+ * from the use of this software.
+ */
+
+#include <libpkgconf/stdinc.h>
+#include <libpkgconf/libpkgconf.h>
+
+/*
+ * !doc
+ *
+ * libpkgconf `dependency` module
+ * ==============================
+ *
+ * The `dependency` module provides support for building `dependency lists` (the basic component of the overall `dependency graph`) and
+ * `dependency nodes` which store dependency information.
+ */
+
+typedef enum {
+	OUTSIDE_MODULE = 0,
+	INSIDE_MODULE_NAME = 1,
+	BEFORE_OPERATOR = 2,
+	INSIDE_OPERATOR = 3,
+	AFTER_OPERATOR = 4,
+	INSIDE_VERSION = 5
+} parse_state_t;
+
+#define DEBUG_PARSE 0
+
+static const char *
+dependency_to_str(const pkgconf_dependency_t *dep, char *buf, size_t buflen)
+{
+	pkgconf_strlcpy(buf, dep->package, buflen);
+	if (dep->version != NULL)
+	{
+		pkgconf_strlcat(buf, " ", buflen);
+		pkgconf_strlcat(buf, pkgconf_pkg_get_comparator(dep), buflen);
+		pkgconf_strlcat(buf, " ", buflen);
+		pkgconf_strlcat(buf, dep->version, buflen);
+	}
+
+	return buf;
+}
+
+static inline pkgconf_dependency_t *
+pkgconf_dependency_addraw(const pkgconf_client_t *client, pkgconf_list_t *list, const char *package, size_t package_sz, const char *version, size_t version_sz, pkgconf_pkg_comparator_t compare)
+{
+	pkgconf_dependency_t *dep;
+	char depbuf[PKGCONF_BUFSIZE];
+
+	dep = calloc(sizeof(pkgconf_dependency_t), 1);
+	dep->package = pkgconf_strndup(package, package_sz);
+
+	if (version_sz != 0)
+		dep->version = pkgconf_strndup(version, version_sz);
+
+	dep->compare = compare;
+
+	PKGCONF_TRACE(client, "added dependency [%s] to list @%p", dependency_to_str(dep, depbuf, sizeof depbuf), list);
+	pkgconf_node_insert_tail(&dep->iter, dep, list);
+
+	return dep;
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: pkgconf_dependency_t *pkgconf_dependency_add(pkgconf_list_t *list, const char *package, const char *version, pkgconf_pkg_comparator_t compare)
+ *
+ *    Adds a parsed dependency to a dependency list as a dependency node.
+ *
+ *    :param pkgconf_client_t* client: The client object that owns the package this dependency list belongs to.
+ *    :param pkgconf_list_t* list: The dependency list to add a dependency node to.
+ *    :param char* package: The package `atom` to set on the dependency node.
+ *    :param char* version: The package `version` to set on the dependency node.
+ *    :param pkgconf_pkg_comparator_t compare: The comparison operator to set on the dependency node.
+ *    :return: A dependency node.
+ *    :rtype: pkgconf_dependency_t *
+ */
+pkgconf_dependency_t *
+pkgconf_dependency_add(const pkgconf_client_t *client, pkgconf_list_t *list, const char *package, const char *version, pkgconf_pkg_comparator_t compare)
+{
+	if (version != NULL)
+		return pkgconf_dependency_addraw(client, list, package, strlen(package), version, strlen(version), compare);
+
+	return pkgconf_dependency_addraw(client, list, package, strlen(package), NULL, 0, compare);
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_dependency_append(pkgconf_list_t *list, pkgconf_dependency_t *tail)
+ *
+ *    Adds a dependency node to a pre-existing dependency list.
+ *
+ *    :param pkgconf_list_t* list: The dependency list to add a dependency node to.
+ *    :param pkgconf_dependency_t* tail: The dependency node to add to the tail of the dependency list.
+ *    :return: nothing
+ */
+void
+pkgconf_dependency_append(pkgconf_list_t *list, pkgconf_dependency_t *tail)
+{
+	pkgconf_node_insert_tail(&tail->iter, tail, list);
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_dependency_free(pkgconf_list_t *list)
+ *
+ *    Release a dependency list and it's child dependency nodes.
+ *
+ *    :param pkgconf_list_t* list: The dependency list to release.
+ *    :return: nothing
+ */
+void
+pkgconf_dependency_free(pkgconf_list_t *list)
+{
+	pkgconf_node_t *node, *next;
+
+	PKGCONF_FOREACH_LIST_ENTRY_SAFE(list->head, next, node)
+	{
+		pkgconf_dependency_t *dep = node->data;
+
+		if (dep->package != NULL)
+			free(dep->package);
+
+		if (dep->version != NULL)
+			free(dep->version);
+
+		free(dep);
+	}
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_dependency_parse_str(pkgconf_list_t *deplist_head, const char *depends)
+ *
+ *    Parse a dependency declaration into a dependency list.
+ *    Commas are counted as whitespace to allow for constructs such as ``@SUBSTVAR@, zlib`` being processed
+ *    into ``, zlib``.
+ *
+ *    :param pkgconf_client_t* client: The client object that owns the package this dependency list belongs to.
+ *    :param pkgconf_list_t* deplist_head: The dependency list to populate with dependency nodes.
+ *    :param char* depends: The dependency data to parse.
+ *    :return: nothing
+ */
+void
+pkgconf_dependency_parse_str(const pkgconf_client_t *client, pkgconf_list_t *deplist_head, const char *depends)
+{
+	parse_state_t state = OUTSIDE_MODULE;
+	pkgconf_pkg_comparator_t compare = PKGCONF_CMP_ANY;
+	char cmpname[PKGCONF_BUFSIZE];
+	char buf[PKGCONF_BUFSIZE];
+	size_t package_sz = 0, version_sz = 0;
+	char *start = buf;
+	char *ptr = buf;
+	char *vstart = NULL;
+	char *package = NULL, *version = NULL;
+	char *cnameptr = cmpname;
+
+	memset(cmpname, '\0', sizeof cmpname);
+
+	pkgconf_strlcpy(buf, depends, sizeof buf);
+	pkgconf_strlcat(buf, " ", sizeof buf);
+
+	while (*ptr)
+	{
+		switch (state)
+		{
+		case OUTSIDE_MODULE:
+			if (!PKGCONF_IS_MODULE_SEPARATOR(*ptr))
+				state = INSIDE_MODULE_NAME;
+
+			break;
+
+		case INSIDE_MODULE_NAME:
+			if (isspace((unsigned int)*ptr))
+			{
+				const char *sptr = ptr;
+
+				while (*sptr && isspace((unsigned int)*sptr))
+					sptr++;
+
+				if (*sptr == '\0')
+					state = OUTSIDE_MODULE;
+				else if (PKGCONF_IS_MODULE_SEPARATOR(*sptr))
+					state = OUTSIDE_MODULE;
+				else if (PKGCONF_IS_OPERATOR_CHAR(*sptr))
+					state = BEFORE_OPERATOR;
+				else
+					state = OUTSIDE_MODULE;
+			}
+			else if (PKGCONF_IS_MODULE_SEPARATOR(*ptr))
+				state = OUTSIDE_MODULE;
+			else if (*(ptr + 1) == '\0')
+			{
+				ptr++;
+				state = OUTSIDE_MODULE;
+			}
+
+			if (state != INSIDE_MODULE_NAME && start != ptr)
+			{
+				char *iter = start;
+
+				while (PKGCONF_IS_MODULE_SEPARATOR(*iter))
+					iter++;
+
+				package = iter;
+				package_sz = ptr - iter;
+				start = ptr;
+			}
+
+			if (state == OUTSIDE_MODULE)
+			{
+				pkgconf_dependency_addraw(client, deplist_head, package, package_sz, NULL, 0, compare);
+
+				compare = PKGCONF_CMP_ANY;
+				package_sz = 0;
+			}
+
+			break;
+
+		case BEFORE_OPERATOR:
+			if (PKGCONF_IS_OPERATOR_CHAR(*ptr))
+			{
+				state = INSIDE_OPERATOR;
+				*cnameptr++ = *ptr;
+			}
+
+			break;
+
+		case INSIDE_OPERATOR:
+			if (!PKGCONF_IS_OPERATOR_CHAR(*ptr))
+			{
+				state = AFTER_OPERATOR;
+				compare = pkgconf_pkg_comparator_lookup_by_name(cmpname);
+			}
+			else
+				*cnameptr++ = *ptr;
+
+			break;
+
+		case AFTER_OPERATOR:
+			if (!isspace((unsigned int)*ptr))
+			{
+				vstart = ptr;
+				state = INSIDE_VERSION;
+			}
+			break;
+
+		case INSIDE_VERSION:
+			if (PKGCONF_IS_MODULE_SEPARATOR(*ptr) || *(ptr + 1) == '\0')
+			{
+				version = vstart;
+				version_sz = ptr - vstart;
+				state = OUTSIDE_MODULE;
+
+				pkgconf_dependency_addraw(client, deplist_head, package, package_sz, version, version_sz, compare);
+
+				compare = PKGCONF_CMP_ANY;
+				cnameptr = cmpname;
+				memset(cmpname, 0, sizeof cmpname);
+				package_sz = 0;
+			}
+
+			if (state == OUTSIDE_MODULE)
+				start = ptr;
+			break;
+		}
+
+		ptr++;
+	}
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_dependency_parse(const pkgconf_client_t *client, pkgconf_pkg_t *pkg, pkgconf_list_t *deplist, const char *depends)
+ *
+ *    Preprocess dependency data and then process that dependency declaration into a dependency list.
+ *    Commas are counted as whitespace to allow for constructs such as ``@SUBSTVAR@, zlib`` being processed
+ *    into ``, zlib``.
+ *
+ *    :param pkgconf_client_t* client: The client object that owns the package this dependency list belongs to.
+ *    :param pkgconf_pkg_t* pkg: The package object that owns this dependency list.
+ *    :param pkgconf_list_t* deplist: The dependency list to populate with dependency nodes.
+ *    :param char* depends: The dependency data to parse.
+ *    :return: nothing
+ */
+void
+pkgconf_dependency_parse(const pkgconf_client_t *client, pkgconf_pkg_t *pkg, pkgconf_list_t *deplist, const char *depends)
+{
+	char *kvdepends = pkgconf_tuple_parse(client, &pkg->vars, depends);
+
+	pkgconf_dependency_parse_str(client, deplist, kvdepends);
+	free(kvdepends);
+}
diff --git a/libpkgconf/fragment.c b/libpkgconf/fragment.c
index b405631..22d6d04 100644
--- a/libpkgconf/fragment.c
+++ b/libpkgconf/fragment.c
@@ -122,7 +122,7 @@ pkgconf_fragment_munge(const pkgconf_client_t *client, char *buf, size_t buflen,
 static inline char *
 pkgconf_fragment_copy_munged(const pkgconf_client_t *client, const char *source)
 {
-	char mungebuf[PKGCONF_BUFSIZE];
+	char mungebuf[PKGCONF_SBUFSIZE];
 	pkgconf_fragment_munge(client, mungebuf, sizeof mungebuf, source, client->sysroot_dir);
 	return strdup(mungebuf);
 }
@@ -158,7 +158,7 @@ pkgconf_fragment_add(const pkgconf_client_t *client, pkgconf_list_t *list, const
 	}
 	else
 	{
-		char mungebuf[PKGCONF_BUFSIZE];
+		char mungebuf[PKGCONF_SBUFSIZE];
 
 		if (list->tail != NULL && list->tail->data != NULL)
 		{
diff --git a/libpkgconf/fragment.c.orig b/libpkgconf/fragment.c.orig
new file mode 100644
index 0000000..b405631
--- /dev/null
+++ b/libpkgconf/fragment.c.orig
@@ -0,0 +1,627 @@
+/*
+ * fragment.c
+ * Management of fragment lists.
+ *
+ * Copyright (c) 2012, 2013, 2014 pkgconf authors (see AUTHORS).
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * This software is provided 'as is' and without any warranty, express or
+ * implied.  In no event shall the authors be liable for any damages arising
+ * from the use of this software.
+ */
+
+#include <libpkgconf/stdinc.h>
+#include <libpkgconf/libpkgconf.h>
+
+/*
+ * !doc
+ *
+ * libpkgconf `fragment` module
+ * ============================
+ *
+ * The `fragment` module provides low-level management and rendering of fragment lists.  A
+ * `fragment list` contains various `fragments` of text (such as ``-I /usr/include``) in a matter
+ * which is composable, mergeable and reorderable.
+ */
+
+struct pkgconf_fragment_check {
+	char *token;
+	size_t len;
+};
+
+static inline bool
+pkgconf_fragment_is_unmergeable(const char *string)
+{
+	static const struct pkgconf_fragment_check check_fragments[] = {
+		{"-framework", 10},
+		{"-isystem", 8},
+		{"-idirafter", 10},
+		{"-pthread", 8},
+		{"-Wa,", 4},
+		{"-Wl,", 4},
+		{"-Wp,", 4},
+		{"-trigraphs", 10},
+		{"-pedantic", 9},
+		{"-ansi", 5},
+		{"-std=", 5},
+		{"-stdlib=", 8},
+		{"-include", 8},
+		{"-nostdinc", 9},
+		{"-nostdlibinc", 12},
+		{"-nobuiltininc", 13},
+	};
+
+	if (*string != '-')
+		return true;
+
+	for (size_t i = 0; i < PKGCONF_ARRAY_SIZE(check_fragments); i++)
+		if (!strncmp(string, check_fragments[i].token, check_fragments[i].len))
+			return true;
+
+	/* only one pair of {-flag, arg} may be merged together */
+	if (strchr(string, ' ') != NULL)
+		return false;
+
+	return false;
+}
+
+static inline bool
+pkgconf_fragment_should_munge(const char *string, const char *sysroot_dir)
+{
+	static const struct pkgconf_fragment_check check_fragments[] = {
+		{"-isystem", 8},
+		{"-idirafter", 10},
+		{"-include", 8},
+	};
+
+	if (*string != '/')
+		return false;
+
+	if (sysroot_dir != NULL && strncmp(sysroot_dir, string, strlen(sysroot_dir)))
+		return true;
+
+	for (size_t i = 0; i < PKGCONF_ARRAY_SIZE(check_fragments); i++)
+		if (!strncmp(string, check_fragments[i].token, check_fragments[i].len))
+			return true;
+
+	return false;
+}
+
+static inline bool
+pkgconf_fragment_is_special(const char *string)
+{
+	if (*string != '-')
+		return true;
+
+	if (!strncmp(string, "-lib:", 5))
+		return true;
+
+	return pkgconf_fragment_is_unmergeable(string);
+}
+
+static inline void
+pkgconf_fragment_munge(const pkgconf_client_t *client, char *buf, size_t buflen, const char *source, const char *sysroot_dir)
+{
+	*buf = '\0';
+
+	if (sysroot_dir == NULL)
+		sysroot_dir = pkgconf_tuple_find_global(client, "pc_sysrootdir");
+
+	if (sysroot_dir != NULL && pkgconf_fragment_should_munge(source, sysroot_dir))
+		pkgconf_strlcat(buf, sysroot_dir, buflen);
+
+	pkgconf_strlcat(buf, source, buflen);
+
+	if (*buf == '/' && !(client->flags & PKGCONF_PKG_PKGF_DONT_RELOCATE_PATHS))
+		pkgconf_path_relocate(buf, buflen);
+}
+
+static inline char *
+pkgconf_fragment_copy_munged(const pkgconf_client_t *client, const char *source)
+{
+	char mungebuf[PKGCONF_BUFSIZE];
+	pkgconf_fragment_munge(client, mungebuf, sizeof mungebuf, source, client->sysroot_dir);
+	return strdup(mungebuf);
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_fragment_add(const pkgconf_client_t *client, pkgconf_list_t *list, const char *string)
+ *
+ *    Adds a `fragment` of text to a `fragment list`, possibly modifying the fragment if a sysroot is set.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client being accessed.
+ *    :param pkgconf_list_t* list: The fragment list.
+ *    :param char* string: The string of text to add as a fragment to the fragment list.
+ *    :return: nothing
+ */
+void
+pkgconf_fragment_add(const pkgconf_client_t *client, pkgconf_list_t *list, const char *string)
+{
+	pkgconf_fragment_t *frag;
+
+	if (*string == '\0')
+		return;
+
+	if (!pkgconf_fragment_is_special(string))
+	{
+		frag = calloc(sizeof(pkgconf_fragment_t), 1);
+
+		frag->type = *(string + 1);
+		frag->data = pkgconf_fragment_copy_munged(client, string + 2);
+
+		PKGCONF_TRACE(client, "added fragment {%c, '%s'} to list @%p", frag->type, frag->data, list);
+	}
+	else
+	{
+		char mungebuf[PKGCONF_BUFSIZE];
+
+		if (list->tail != NULL && list->tail->data != NULL)
+		{
+			pkgconf_fragment_t *parent = list->tail->data;
+
+			/* only attempt to merge 'special' fragments together */
+			if (!parent->type && pkgconf_fragment_is_unmergeable(parent->data))
+			{
+				size_t len;
+				char *newdata;
+
+				pkgconf_fragment_munge(client, mungebuf, sizeof mungebuf, string, NULL);
+
+				len = strlen(parent->data) + strlen(mungebuf) + 2;
+				newdata = malloc(len);
+
+				pkgconf_strlcpy(newdata, parent->data, len);
+				pkgconf_strlcat(newdata, " ", len);
+				pkgconf_strlcat(newdata, mungebuf, len);
+
+				PKGCONF_TRACE(client, "merging '%s' to '%s' to form fragment {'%s'} in list @%p", mungebuf, parent->data, newdata, list);
+
+				free(parent->data);
+				parent->data = newdata;
+
+				/* use a copy operation to force a dedup */
+				pkgconf_node_delete(&parent->iter, list);
+				pkgconf_fragment_copy(client, list, parent, false);
+
+				/* the fragment list now (maybe) has the copied node, so free the original */
+				free(parent->data);
+				free(parent);
+
+				return;
+			}
+		}
+
+		frag = calloc(sizeof(pkgconf_fragment_t), 1);
+
+		frag->type = 0;
+		frag->data = strdup(string);
+
+		PKGCONF_TRACE(client, "created special fragment {'%s'} in list @%p", frag->data, list);
+	}
+
+	pkgconf_node_insert_tail(&frag->iter, frag, list);
+}
+
+static inline pkgconf_fragment_t *
+pkgconf_fragment_lookup(pkgconf_list_t *list, const pkgconf_fragment_t *base)
+{
+	pkgconf_node_t *node;
+
+	PKGCONF_FOREACH_LIST_ENTRY_REVERSE(list->tail, node)
+	{
+		pkgconf_fragment_t *frag = node->data;
+
+		if (base->type != frag->type)
+			continue;
+
+		if (!strcmp(base->data, frag->data))
+			return frag;
+	}
+
+	return NULL;
+}
+
+static inline bool
+pkgconf_fragment_can_merge_back(const pkgconf_fragment_t *base, unsigned int flags, bool is_private)
+{
+	(void) flags;
+
+	if (base->type == 'l')
+	{
+		if (is_private)
+			return false;
+
+		return true;
+	}
+
+	if (base->type == 'F')
+		return false;
+	if (base->type == 'L')
+		return false;
+	if (base->type == 'I')
+		return false;
+
+	return true;
+}
+
+static inline bool
+pkgconf_fragment_can_merge(const pkgconf_fragment_t *base, unsigned int flags, bool is_private)
+{
+	(void) flags;
+
+	if (is_private)
+		return false;
+
+	return pkgconf_fragment_is_unmergeable(base->data);
+}
+
+static inline pkgconf_fragment_t *
+pkgconf_fragment_exists(pkgconf_list_t *list, const pkgconf_fragment_t *base, unsigned int flags, bool is_private)
+{
+	if (!pkgconf_fragment_can_merge_back(base, flags, is_private))
+		return NULL;
+
+	if (!pkgconf_fragment_can_merge(base, flags, is_private))
+		return NULL;
+
+	return pkgconf_fragment_lookup(list, base);
+}
+
+static inline bool
+pkgconf_fragment_should_merge(const pkgconf_fragment_t *base)
+{
+	const pkgconf_fragment_t *parent;
+
+	/* if we are the first fragment, that means the next fragment is the same, so it's always safe. */
+	if (base->iter.prev == NULL)
+		return true;
+
+	/* this really shouldn't ever happen, but handle it */
+	parent = base->iter.prev->data;
+	if (parent == NULL)
+		return true;
+
+	switch (parent->type)
+	{
+	case 'l':
+	case 'L':
+	case 'I':
+		return true;
+	default:
+		return !base->type || parent->type == base->type;
+	}
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: bool pkgconf_fragment_has_system_dir(const pkgconf_client_t *client, const pkgconf_fragment_t *frag)
+ *
+ *    Checks if a `fragment` contains a `system path`.  System paths are detected at compile time and optionally overridden by
+ *    the ``PKG_CONFIG_SYSTEM_INCLUDE_PATH`` and ``PKG_CONFIG_SYSTEM_LIBRARY_PATH`` environment variables.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client object the fragment belongs to.
+ *    :param pkgconf_fragment_t* frag: The fragment being checked.
+ *    :return: true if the fragment contains a system path, else false
+ *    :rtype: bool
+ */
+bool
+pkgconf_fragment_has_system_dir(const pkgconf_client_t *client, const pkgconf_fragment_t *frag)
+{
+	const pkgconf_list_t *check_paths = NULL;
+
+	switch (frag->type)
+	{
+	case 'L':
+		check_paths = &client->filter_libdirs;
+		break;
+	case 'I':
+		check_paths = &client->filter_includedirs;
+		break;
+	default:
+		return false;
+	}
+
+	return pkgconf_path_match_list(frag->data, check_paths);
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_fragment_copy(const pkgconf_client_t *client, pkgconf_list_t *list, const pkgconf_fragment_t *base, bool is_private)
+ *
+ *    Copies a `fragment` to another `fragment list`, possibly removing a previous copy of the `fragment`
+ *    in a process known as `mergeback`.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client being accessed.
+ *    :param pkgconf_list_t* list: The list the fragment is being added to.
+ *    :param pkgconf_fragment_t* base: The fragment being copied.
+ *    :param bool is_private: Whether the fragment list is a `private` fragment list (static linking).
+ *    :return: nothing
+ */
+void
+pkgconf_fragment_copy(const pkgconf_client_t *client, pkgconf_list_t *list, const pkgconf_fragment_t *base, bool is_private)
+{
+	pkgconf_fragment_t *frag;
+
+	if ((frag = pkgconf_fragment_exists(list, base, client->flags, is_private)) != NULL)
+	{
+		if (pkgconf_fragment_should_merge(frag))
+			pkgconf_fragment_delete(list, frag);
+	}
+	else if (!is_private && !pkgconf_fragment_can_merge_back(base, client->flags, is_private) && (pkgconf_fragment_lookup(list, base) != NULL))
+		return;
+
+	frag = calloc(sizeof(pkgconf_fragment_t), 1);
+
+	frag->type = base->type;
+	frag->data = strdup(base->data);
+
+	pkgconf_node_insert_tail(&frag->iter, frag, list);
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_fragment_filter(const pkgconf_client_t *client, pkgconf_list_t *dest, pkgconf_list_t *src, pkgconf_fragment_filter_func_t filter_func)
+ *
+ *    Copies a `fragment list` to another `fragment list` which match a user-specified filtering function.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client being accessed.
+ *    :param pkgconf_list_t* dest: The destination list.
+ *    :param pkgconf_list_t* src: The source list.
+ *    :param pkgconf_fragment_filter_func_t filter_func: The filter function to use.
+ *    :param void* data: Optional data to pass to the filter function.
+ *    :return: nothing
+ */
+void
+pkgconf_fragment_filter(const pkgconf_client_t *client, pkgconf_list_t *dest, pkgconf_list_t *src, pkgconf_fragment_filter_func_t filter_func, void *data)
+{
+	pkgconf_node_t *node;
+
+	PKGCONF_FOREACH_LIST_ENTRY(src->head, node)
+	{
+		pkgconf_fragment_t *frag = node->data;
+
+		if (filter_func(client, frag, data))
+			pkgconf_fragment_copy(client, dest, frag, true);
+	}
+}
+
+static inline char *
+fragment_escape(const char *src)
+{
+	ssize_t outlen = strlen(src) + 10;
+	char *out = calloc(outlen, 1);
+	char *dst = out;
+
+	while (*src)
+	{
+		if (((*src < ' ') ||
+		    (*src > ' ' && *src < '$') ||
+		    (*src > '$' && *src < '(') ||
+		    (*src > ')' && *src < '+') ||
+		    (*src > ':' && *src < '=') ||
+		    (*src > '=' && *src < '@') ||
+		    (*src > 'Z' && *src < '^') ||
+		    (*src == '`') ||
+		    (*src > 'z' && *src < '~') ||
+		    (*src > '~')) && *src != '\\')
+			*dst++ = '\\';
+
+		*dst++ = *src++;
+
+		if ((ptrdiff_t)(dst - out) + 2 > outlen)
+		{
+			outlen *= 2;
+			out = realloc(out, outlen);
+		}
+	}
+
+	*dst = 0;
+	return out;
+}
+
+static inline size_t
+pkgconf_fragment_len(const pkgconf_fragment_t *frag, bool escape)
+{
+	size_t len = 1;
+
+	if (frag->type)
+		len += 2;
+
+	if (frag->data != NULL)
+	{
+		if (!escape)
+			len += strlen(frag->data);
+		else
+		{
+			char *tmp = fragment_escape(frag->data);
+			len += strlen(tmp);
+			free(tmp);
+		}
+	}
+
+	return len;
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: size_t pkgconf_fragment_render_len(const pkgconf_list_t *list)
+ *
+ *    Calculates the required memory to store a `fragment list` when rendered as a string.
+ *
+ *    :param pkgconf_list_t* list: The `fragment list` being rendered.
+ *    :param bool escape: Whether or not to escape special shell characters.
+ *    :return: the amount of bytes required to represent the `fragment list` when rendered
+ *    :rtype: size_t
+ */
+size_t
+pkgconf_fragment_render_len(const pkgconf_list_t *list, bool escape)
+{
+	size_t out = 1;		/* trailing nul */
+	pkgconf_node_t *node;
+
+	PKGCONF_FOREACH_LIST_ENTRY(list->head, node)
+	{
+		const pkgconf_fragment_t *frag = node->data;
+		out += pkgconf_fragment_len(frag, escape);
+	}
+
+	return out;
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_fragment_render_buf(const pkgconf_list_t *list, char *buf, size_t buflen)
+ *
+ *    Renders a `fragment list` into a buffer.
+ *
+ *    :param pkgconf_list_t* list: The `fragment list` being rendered.
+ *    :param char* buf: The buffer to render the fragment list into.
+ *    :param size_t buflen: The length of the buffer.
+ *    :param bool escape: Whether or not to escape special shell characters.
+ *    :return: nothing
+ */
+void
+pkgconf_fragment_render_buf(const pkgconf_list_t *list, char *buf, size_t buflen, bool escape)
+{
+	pkgconf_node_t *node;
+	char *bptr = buf;
+
+	memset(buf, 0, buflen);
+
+	PKGCONF_FOREACH_LIST_ENTRY(list->head, node)
+	{
+		const pkgconf_fragment_t *frag = node->data;
+		size_t buf_remaining = buflen - (bptr - buf);
+
+		if (pkgconf_fragment_len(frag, escape) > buf_remaining)
+			break;
+
+		if (frag->type)
+		{
+			*bptr++ = '-';
+			*bptr++ = frag->type;
+		}
+
+		if (frag->data)
+		{
+			if (!escape)
+				bptr += pkgconf_strlcpy(bptr, frag->data, buf_remaining);
+			else
+			{
+				char *tmp = fragment_escape(frag->data);
+				bptr += pkgconf_strlcpy(bptr, tmp, buf_remaining);
+				free(tmp);
+			}
+		}
+
+		*bptr++ = ' ';
+	}
+
+	*bptr = '\0';
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: char *pkgconf_fragment_render(const pkgconf_list_t *list)
+ *
+ *    Allocate memory and render a `fragment list` into it.
+ *
+ *    :param pkgconf_list_t* list: The `fragment list` being rendered.
+ *    :param bool escape: Whether or not to escape special shell characters.
+ *    :return: An allocated string containing the rendered `fragment list`.
+ *    :rtype: char *
+ */
+char *
+pkgconf_fragment_render(const pkgconf_list_t *list, bool escape)
+{
+	size_t buflen = pkgconf_fragment_render_len(list, escape);
+	char *buf = calloc(1, buflen);
+
+	pkgconf_fragment_render_buf(list, buf, buflen, escape);
+
+	return buf;
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_fragment_delete(pkgconf_list_t *list, pkgconf_fragment_t *node)
+ *
+ *    Delete a `fragment node` from a `fragment list`.
+ *
+ *    :param pkgconf_list_t* list: The `fragment list` to delete from.
+ *    :param pkgconf_fragment_t* node: The `fragment node` to delete.
+ *    :return: nothing
+ */
+void
+pkgconf_fragment_delete(pkgconf_list_t *list, pkgconf_fragment_t *node)
+{
+	pkgconf_node_delete(&node->iter, list);
+
+	free(node->data);
+	free(node);
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_fragment_free(pkgconf_list_t *list)
+ *
+ *    Delete an entire `fragment list`.
+ *
+ *    :param pkgconf_list_t* list: The `fragment list` to delete.
+ *    :return: nothing
+ */
+void
+pkgconf_fragment_free(pkgconf_list_t *list)
+{
+	pkgconf_node_t *node, *next;
+
+	PKGCONF_FOREACH_LIST_ENTRY_SAFE(list->head, next, node)
+	{
+		pkgconf_fragment_t *frag = node->data;
+
+		free(frag->data);
+		free(frag);
+	}
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_fragment_parse(const pkgconf_client_t *client, pkgconf_list_t *list, pkgconf_list_t *vars, const char *value)
+ *
+ *    Parse a string into a `fragment list`.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client being accessed.
+ *    :param pkgconf_list_t* list: The `fragment list` to add the fragment entries to.
+ *    :param pkgconf_list_t* vars: A list of variables to use for variable substitution.
+ *    :param char* value: The string to parse into fragments.
+ *    :return: nothing
+ */
+void
+pkgconf_fragment_parse(const pkgconf_client_t *client, pkgconf_list_t *list, pkgconf_list_t *vars, const char *value)
+{
+	int i, argc;
+	char **argv;
+	char *repstr = pkgconf_tuple_parse(client, vars, value);
+
+	pkgconf_argv_split(repstr, &argc, &argv);
+
+	for (i = 0; i < argc; i++)
+		pkgconf_fragment_add(client, list, argv[i]);
+
+	pkgconf_argv_free(argv);
+	free(repstr);
+}
diff --git a/libpkgconf/libpkgconf.h b/libpkgconf/libpkgconf.h
index d7fe911..66b4f54 100644
--- a/libpkgconf/libpkgconf.h
+++ b/libpkgconf/libpkgconf.h
@@ -41,8 +41,6 @@ extern "C" {
 #define PKG_DIR_SEP_S   '/'
 #endif
 
-#define PKGCONF_BUFSIZE	(65535)
-
 typedef enum {
 	PKGCONF_CMP_NOT_EQUAL,
 	PKGCONF_CMP_ANY,
diff --git a/libpkgconf/libpkgconf.h.orig b/libpkgconf/libpkgconf.h.orig
new file mode 100644
index 0000000..d7fe911
--- /dev/null
+++ b/libpkgconf/libpkgconf.h.orig
@@ -0,0 +1,331 @@
+/*
+ * libpkgconf.h
+ * Global include file for everything in libpkgconf.
+ *
+ * Copyright (c) 2011, 2015 pkgconf authors (see AUTHORS).
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * This software is provided 'as is' and without any warranty, express or
+ * implied.  In no event shall the authors be liable for any damages arising
+ * from the use of this software.
+ */
+
+#ifndef LIBPKGCONF__LIBPKGCONF_H
+#define LIBPKGCONF__LIBPKGCONF_H
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdbool.h>
+#include <libpkgconf/iter.h>
+#include <libpkgconf/bsdstubs.h>
+#include <libpkgconf/libpkgconf-api.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* pkg-config uses ';' on win32 as ':' is part of path */
+#ifdef _WIN32
+#define PKG_CONFIG_PATH_SEP_S   ";"
+#else
+#define PKG_CONFIG_PATH_SEP_S   ":"
+#endif
+
+#ifdef _WIN32
+#define PKG_DIR_SEP_S   '\\'
+#else
+#define PKG_DIR_SEP_S   '/'
+#endif
+
+#define PKGCONF_BUFSIZE	(65535)
+
+typedef enum {
+	PKGCONF_CMP_NOT_EQUAL,
+	PKGCONF_CMP_ANY,
+	PKGCONF_CMP_LESS_THAN,
+	PKGCONF_CMP_LESS_THAN_EQUAL,
+	PKGCONF_CMP_EQUAL,
+	PKGCONF_CMP_GREATER_THAN,
+	PKGCONF_CMP_GREATER_THAN_EQUAL
+} pkgconf_pkg_comparator_t;
+
+#define PKGCONF_CMP_COUNT 7
+
+typedef struct pkgconf_pkg_ pkgconf_pkg_t;
+typedef struct pkgconf_dependency_ pkgconf_dependency_t;
+typedef struct pkgconf_tuple_ pkgconf_tuple_t;
+typedef struct pkgconf_fragment_ pkgconf_fragment_t;
+typedef struct pkgconf_path_ pkgconf_path_t;
+typedef struct pkgconf_client_ pkgconf_client_t;
+
+#define PKGCONF_ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
+
+#define PKGCONF_FOREACH_LIST_ENTRY(head, value) \
+	for ((value) = (head); (value) != NULL; (value) = (value)->next)
+
+#define PKGCONF_FOREACH_LIST_ENTRY_SAFE(head, nextiter, value) \
+	for ((value) = (head), (nextiter) = (head) != NULL ? (head)->next : NULL; (value) != NULL; (value) = (nextiter), (nextiter) = (nextiter) != NULL ? (nextiter)->next : NULL)
+
+#define PKGCONF_FOREACH_LIST_ENTRY_REVERSE(tail, value) \
+	for ((value) = (tail); (value) != NULL; (value) = (value)->prev)
+
+struct pkgconf_fragment_ {
+	pkgconf_node_t iter;
+
+	char type;
+	char *data;
+};
+
+struct pkgconf_dependency_ {
+	pkgconf_node_t iter;
+
+	char *package;
+	pkgconf_pkg_comparator_t compare;
+	char *version;
+	pkgconf_pkg_t *parent;
+};
+
+struct pkgconf_tuple_ {
+	pkgconf_node_t iter;
+
+	char *key;
+	char *value;
+};
+
+struct pkgconf_path_ {
+	pkgconf_node_t lnode;
+
+	char *path;
+	void *handle_path;
+	void *handle_device;
+};
+
+#define PKGCONF_PKG_PROPF_NONE			0x00
+#define PKGCONF_PKG_PROPF_STATIC		0x01
+#define PKGCONF_PKG_PROPF_CACHED		0x02
+#define PKGCONF_PKG_PROPF_SEEN			0x04
+#define PKGCONF_PKG_PROPF_UNINSTALLED		0x08
+#define PKGCONF_PKG_PROPF_VIRTUAL		0x10
+
+struct pkgconf_pkg_ {
+	pkgconf_node_t cache_iter;
+
+	int refcount;
+	char *id;
+	char *filename;
+	char *realname;
+	char *version;
+	char *description;
+	char *url;
+	char *pc_filedir;
+
+	pkgconf_list_t libs;
+	pkgconf_list_t libs_private;
+	pkgconf_list_t cflags;
+	pkgconf_list_t cflags_private;
+
+	pkgconf_list_t requires;
+	pkgconf_list_t requires_private;
+	pkgconf_list_t conflicts;
+	pkgconf_list_t provides;
+
+	pkgconf_list_t vars;
+
+	unsigned int flags;
+};
+
+typedef bool (*pkgconf_pkg_iteration_func_t)(const pkgconf_pkg_t *pkg, void *data);
+typedef void (*pkgconf_pkg_traverse_func_t)(pkgconf_client_t *client, pkgconf_pkg_t *pkg, void *data);
+typedef bool (*pkgconf_queue_apply_func_t)(pkgconf_client_t *client, pkgconf_pkg_t *world, void *data, int maxdepth);
+typedef bool (*pkgconf_error_handler_func_t)(const char *msg, const pkgconf_client_t *client, const void *data);
+
+struct pkgconf_client_ {
+	pkgconf_list_t dir_list;
+	pkgconf_list_t pkg_cache;
+
+	pkgconf_list_t filter_libdirs;
+	pkgconf_list_t filter_includedirs;
+
+	pkgconf_list_t global_vars;
+
+	void *error_handler_data;
+	void *warn_handler_data;
+	void *trace_handler_data;
+
+	pkgconf_error_handler_func_t error_handler;
+	pkgconf_error_handler_func_t warn_handler;
+	pkgconf_error_handler_func_t trace_handler;
+
+	FILE *auditf;
+
+	char *sysroot_dir;
+	char *buildroot_dir;
+
+	unsigned int flags;
+
+	char *prefix_varname;
+
+	bool already_sent_notice;
+};
+
+/* client.c */
+PKGCONF_API void pkgconf_client_init(pkgconf_client_t *client, pkgconf_error_handler_func_t error_handler, void *error_handler_data);
+PKGCONF_API pkgconf_client_t * pkgconf_client_new(pkgconf_error_handler_func_t error_handler, void *error_handler_data);
+PKGCONF_API void pkgconf_client_deinit(pkgconf_client_t *client);
+PKGCONF_API void pkgconf_client_free(pkgconf_client_t *client);
+PKGCONF_API const char *pkgconf_client_get_sysroot_dir(const pkgconf_client_t *client);
+PKGCONF_API void pkgconf_client_set_sysroot_dir(pkgconf_client_t *client, const char *sysroot_dir);
+PKGCONF_API const char *pkgconf_client_get_buildroot_dir(const pkgconf_client_t *client);
+PKGCONF_API void pkgconf_client_set_buildroot_dir(pkgconf_client_t *client, const char *buildroot_dir);
+PKGCONF_API unsigned int pkgconf_client_get_flags(const pkgconf_client_t *client);
+PKGCONF_API void pkgconf_client_set_flags(pkgconf_client_t *client, unsigned int flags);
+PKGCONF_API const char *pkgconf_client_get_prefix_varname(const pkgconf_client_t *client);
+PKGCONF_API void pkgconf_client_set_prefix_varname(pkgconf_client_t *client, const char *prefix_varname);
+PKGCONF_API pkgconf_error_handler_func_t pkgconf_client_get_warn_handler(const pkgconf_client_t *client);
+PKGCONF_API void pkgconf_client_set_warn_handler(pkgconf_client_t *client, pkgconf_error_handler_func_t warn_handler, void *warn_handler_data);
+PKGCONF_API pkgconf_error_handler_func_t pkgconf_client_get_error_handler(const pkgconf_client_t *client);
+PKGCONF_API void pkgconf_client_set_error_handler(pkgconf_client_t *client, pkgconf_error_handler_func_t error_handler, void *error_handler_data);
+PKGCONF_API pkgconf_error_handler_func_t pkgconf_client_get_trace_handler(const pkgconf_client_t *client);
+PKGCONF_API void pkgconf_client_set_trace_handler(pkgconf_client_t *client, pkgconf_error_handler_func_t trace_handler, void *trace_handler_data);
+
+#define PKGCONF_IS_MODULE_SEPARATOR(c) ((c) == ',' || isspace ((unsigned int)(c)))
+#define PKGCONF_IS_OPERATOR_CHAR(c) ((c) == '<' || (c) == '>' || (c) == '!' || (c) == '=')
+
+#define PKGCONF_PKG_PKGF_NONE				0x0000
+#define PKGCONF_PKG_PKGF_SEARCH_PRIVATE			0x0001
+#define PKGCONF_PKG_PKGF_ENV_ONLY			0x0002
+#define PKGCONF_PKG_PKGF_NO_UNINSTALLED			0x0004
+#define PKGCONF_PKG_PKGF_SKIP_ROOT_VIRTUAL		0x0008
+#define PKGCONF_PKG_PKGF_MERGE_PRIVATE_FRAGMENTS	0x0010
+#define PKGCONF_PKG_PKGF_SKIP_CONFLICTS			0x0020
+#define PKGCONF_PKG_PKGF_NO_CACHE			0x0040
+#define PKGCONF_PKG_PKGF_SKIP_ERRORS			0x0080
+#define PKGCONF_PKG_PKGF_ITER_PKG_IS_PRIVATE		0x0100
+#define PKGCONF_PKG_PKGF_SKIP_PROVIDES			0x0200
+#define PKGCONF_PKG_PKGF_REDEFINE_PREFIX		0x0400
+#define PKGCONF_PKG_PKGF_DONT_RELOCATE_PATHS		0x0800
+#define PKGCONF_PKG_PKGF_SIMPLIFY_ERRORS		0x1000
+
+#define PKGCONF_PKG_ERRF_OK			0x0
+#define PKGCONF_PKG_ERRF_PACKAGE_NOT_FOUND	0x1
+#define PKGCONF_PKG_ERRF_PACKAGE_VER_MISMATCH	0x2
+#define PKGCONF_PKG_ERRF_PACKAGE_CONFLICT	0x4
+#define PKGCONF_PKG_ERRF_DEPGRAPH_BREAK		0x8
+
+/* pkg.c */
+#if defined(__GNUC__) || defined(__INTEL_COMPILER)
+#define PRINTFLIKE(fmtarg, firstvararg) \
+        __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
+#define DEPRECATED \
+        __attribute__((deprecated))
+#else
+#define PRINTFLIKE(fmtarg, firstvararg)
+#define DEPRECATED
+#endif /* defined(__INTEL_COMPILER) || defined(__GNUC__) */
+
+PKGCONF_API bool pkgconf_error(const pkgconf_client_t *client, const char *format, ...) PRINTFLIKE(2, 3);
+PKGCONF_API bool pkgconf_warn(const pkgconf_client_t *client, const char *format, ...) PRINTFLIKE(2, 3);
+PKGCONF_API bool pkgconf_trace(const pkgconf_client_t *client, const char *filename, size_t lineno, const char *funcname, const char *format, ...) PRINTFLIKE(5, 6);
+PKGCONF_API bool pkgconf_default_error_handler(const char *msg, const pkgconf_client_t *client, const void *data);
+
+#if defined(__GNUC__) || defined(__INTEL_COMPILER)
+#define PKGCONF_TRACE(client, ...) do { \
+		pkgconf_trace(client, __FILE__, __LINE__, __PRETTY_FUNCTION__, __VA_ARGS__); \
+	} while (0);
+#else
+#define PKGCONF_TRACE(client, ...) do { \
+		pkgconf_trace(client, __FILE__, __LINE__, __func__, __VA_ARGS__); \
+	} while (0);
+#endif
+
+PKGCONF_API pkgconf_pkg_t *pkgconf_pkg_ref(const pkgconf_client_t *client, pkgconf_pkg_t *pkg);
+PKGCONF_API void pkgconf_pkg_unref(pkgconf_client_t *client, pkgconf_pkg_t *pkg);
+PKGCONF_API void pkgconf_pkg_free(pkgconf_client_t *client, pkgconf_pkg_t *pkg);
+PKGCONF_API pkgconf_pkg_t *pkgconf_pkg_find(pkgconf_client_t *client, const char *name);
+PKGCONF_API unsigned int pkgconf_pkg_traverse(pkgconf_client_t *client, pkgconf_pkg_t *root, pkgconf_pkg_traverse_func_t func, void *data, int maxdepth);
+PKGCONF_API unsigned int pkgconf_pkg_verify_graph(pkgconf_client_t *client, pkgconf_pkg_t *root, int depth);
+PKGCONF_API pkgconf_pkg_t *pkgconf_pkg_verify_dependency(pkgconf_client_t *client, pkgconf_dependency_t *pkgdep, unsigned int *eflags);
+PKGCONF_API const char *pkgconf_pkg_get_comparator(const pkgconf_dependency_t *pkgdep);
+PKGCONF_API unsigned int pkgconf_pkg_cflags(pkgconf_client_t *client, pkgconf_pkg_t *root, pkgconf_list_t *list, int maxdepth);
+PKGCONF_API unsigned int pkgconf_pkg_libs(pkgconf_client_t *client, pkgconf_pkg_t *root, pkgconf_list_t *list, int maxdepth);
+PKGCONF_API pkgconf_pkg_comparator_t pkgconf_pkg_comparator_lookup_by_name(const char *name);
+PKGCONF_API pkgconf_pkg_t *pkgconf_builtin_pkg_get(const char *name);
+
+PKGCONF_API int pkgconf_compare_version(const char *a, const char *b);
+PKGCONF_API pkgconf_pkg_t *pkgconf_scan_all(pkgconf_client_t *client, void *ptr, pkgconf_pkg_iteration_func_t func);
+PKGCONF_API void pkgconf_pkg_dir_list_build(pkgconf_client_t *client);
+
+/* parse.c */
+PKGCONF_API pkgconf_pkg_t *pkgconf_pkg_new_from_file(pkgconf_client_t *client, const char *path, FILE *f);
+PKGCONF_API void pkgconf_dependency_parse_str(const pkgconf_client_t *client, pkgconf_list_t *deplist_head, const char *depends);
+PKGCONF_API void pkgconf_dependency_parse(const pkgconf_client_t *client, pkgconf_pkg_t *pkg, pkgconf_list_t *deplist_head, const char *depends);
+PKGCONF_API void pkgconf_dependency_append(pkgconf_list_t *list, pkgconf_dependency_t *tail);
+PKGCONF_API void pkgconf_dependency_free(pkgconf_list_t *list);
+PKGCONF_API pkgconf_dependency_t *pkgconf_dependency_add(const pkgconf_client_t *client, pkgconf_list_t *list, const char *package, const char *version, pkgconf_pkg_comparator_t compare);
+
+/* argvsplit.c */
+PKGCONF_API int pkgconf_argv_split(const char *src, int *argc, char ***argv);
+PKGCONF_API void pkgconf_argv_free(char **argv);
+
+/* fragment.c */
+typedef bool (*pkgconf_fragment_filter_func_t)(const pkgconf_client_t *client, const pkgconf_fragment_t *frag, void *data);
+PKGCONF_API void pkgconf_fragment_parse(const pkgconf_client_t *client, pkgconf_list_t *list, pkgconf_list_t *vars, const char *value);
+PKGCONF_API void pkgconf_fragment_add(const pkgconf_client_t *client, pkgconf_list_t *list, const char *string);
+PKGCONF_API void pkgconf_fragment_copy(const pkgconf_client_t *client, pkgconf_list_t *list, const pkgconf_fragment_t *base, bool is_private);
+PKGCONF_API void pkgconf_fragment_delete(pkgconf_list_t *list, pkgconf_fragment_t *node);
+PKGCONF_API void pkgconf_fragment_free(pkgconf_list_t *list);
+PKGCONF_API void pkgconf_fragment_filter(const pkgconf_client_t *client, pkgconf_list_t *dest, pkgconf_list_t *src, pkgconf_fragment_filter_func_t filter_func, void *data);
+PKGCONF_API size_t pkgconf_fragment_render_len(const pkgconf_list_t *list, bool escape);
+PKGCONF_API void pkgconf_fragment_render_buf(const pkgconf_list_t *list, char *buf, size_t len, bool escape);
+PKGCONF_API char *pkgconf_fragment_render(const pkgconf_list_t *list, bool escape);
+PKGCONF_API bool pkgconf_fragment_has_system_dir(const pkgconf_client_t *client, const pkgconf_fragment_t *frag);
+
+/* fileio.c */
+PKGCONF_API char *pkgconf_fgetline(char *line, size_t size, FILE *stream);
+
+/* tuple.c */
+PKGCONF_API pkgconf_tuple_t *pkgconf_tuple_add(const pkgconf_client_t *client, pkgconf_list_t *parent, const char *key, const char *value, bool parse);
+PKGCONF_API char *pkgconf_tuple_find(const pkgconf_client_t *client, pkgconf_list_t *list, const char *key);
+PKGCONF_API char *pkgconf_tuple_parse(const pkgconf_client_t *client, pkgconf_list_t *list, const char *value);
+PKGCONF_API void pkgconf_tuple_free(pkgconf_list_t *list);
+PKGCONF_API void pkgconf_tuple_free_entry(pkgconf_tuple_t *tuple, pkgconf_list_t *list);
+PKGCONF_API void pkgconf_tuple_add_global(pkgconf_client_t *client, const char *key, const char *value);
+PKGCONF_API char *pkgconf_tuple_find_global(const pkgconf_client_t *client, const char *key);
+PKGCONF_API void pkgconf_tuple_free_global(pkgconf_client_t *client);
+PKGCONF_API void pkgconf_tuple_define_global(pkgconf_client_t *client, const char *kv);
+
+/* queue.c */
+PKGCONF_API void pkgconf_queue_push(pkgconf_list_t *list, const char *package);
+PKGCONF_API bool pkgconf_queue_compile(pkgconf_client_t *client, pkgconf_pkg_t *world, pkgconf_list_t *list);
+PKGCONF_API void pkgconf_queue_free(pkgconf_list_t *list);
+PKGCONF_API bool pkgconf_queue_apply(pkgconf_client_t *client, pkgconf_list_t *list, pkgconf_queue_apply_func_t func, int maxdepth, void *data);
+PKGCONF_API bool pkgconf_queue_validate(pkgconf_client_t *client, pkgconf_list_t *list, int maxdepth);
+
+/* cache.c */
+PKGCONF_API pkgconf_pkg_t *pkgconf_cache_lookup(const pkgconf_client_t *client, const char *id);
+PKGCONF_API void pkgconf_cache_add(pkgconf_client_t *client, pkgconf_pkg_t *pkg);
+PKGCONF_API void pkgconf_cache_remove(pkgconf_client_t *client, pkgconf_pkg_t *pkg);
+PKGCONF_API void pkgconf_cache_free(pkgconf_client_t *client);
+
+/* audit.c */
+PKGCONF_API void pkgconf_audit_set_log(pkgconf_client_t *client, FILE *auditf);
+PKGCONF_API void pkgconf_audit_log(pkgconf_client_t *client, const char *format, ...) PRINTFLIKE(2, 3);
+PKGCONF_API void pkgconf_audit_log_dependency(pkgconf_client_t *client, const pkgconf_pkg_t *dep, const pkgconf_dependency_t *depnode);
+
+/* path.c */
+PKGCONF_API void pkgconf_path_add(const char *text, pkgconf_list_t *dirlist, bool filter);
+PKGCONF_API size_t pkgconf_path_split(const char *text, pkgconf_list_t *dirlist, bool filter);
+PKGCONF_API size_t pkgconf_path_build_from_environ(const char *envvarname, const char *fallback, pkgconf_list_t *dirlist, bool filter);
+PKGCONF_API bool pkgconf_path_match_list(const char *path, const pkgconf_list_t *dirlist);
+PKGCONF_API void pkgconf_path_free(pkgconf_list_t *dirlist);
+PKGCONF_API bool pkgconf_path_relocate(char *buf, size_t buflen);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/libpkgconf/path.c b/libpkgconf/path.c
index 5b7aa1c..7f90928 100644
--- a/libpkgconf/path.c
+++ b/libpkgconf/path.c
@@ -78,7 +78,7 @@ void
 pkgconf_path_add(const char *text, pkgconf_list_t *dirlist, bool filter)
 {
 	pkgconf_path_t *node;
-	char path[PKGCONF_BUFSIZE];
+	char path[PKGCONF_SBUFSIZE];
 
 #ifdef PKGCONF_CACHE_INODES
 	struct stat st;
@@ -89,7 +89,7 @@ pkgconf_path_add(const char *text, pkgconf_list_t *dirlist, bool filter)
 			return;
 		if (S_ISLNK(st.st_mode))
 		{
-			char linkdest[PKGCONF_BUFSIZE];
+			char linkdest[PKGCONF_SBUFSIZE];
 			ssize_t len = readlink(text, linkdest, sizeof(linkdest));
 
 			if (len != -1 && (size_t)len < sizeof(linkdest) &&
@@ -201,7 +201,7 @@ bool
 pkgconf_path_match_list(const char *path, const pkgconf_list_t *dirlist)
 {
 	pkgconf_node_t *n = NULL;
-	char relocated[PKGCONF_BUFSIZE];
+	char relocated[PKGCONF_SBUFSIZE];
 	const char *cpath = path;
 
 	pkgconf_strlcpy(relocated, path, sizeof relocated);
diff --git a/libpkgconf/path.c.orig b/libpkgconf/path.c.orig
new file mode 100644
index 0000000..5b7aa1c
--- /dev/null
+++ b/libpkgconf/path.c.orig
@@ -0,0 +1,327 @@
+/*
+ * path.c
+ * filesystem path management
+ *
+ * Copyright (c) 2016 pkgconf authors (see AUTHORS).
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * This software is provided 'as is' and without any warranty, express or
+ * implied.  In no event shall the authors be liable for any damages arising
+ * from the use of this software.
+ */
+
+#include <libpkgconf/stdinc.h>
+#include <libpkgconf/libpkgconf.h>
+#include <libpkgconf/config.h>
+
+#if defined(HAVE_CYGWIN_CONV_PATH) && defined(__MSYS__)
+# include <sys/cygwin.h>
+#endif
+
+#if defined(HAVE_SYS_STAT_H) && ! defined(_WIN32)
+# include <sys/stat.h>
+# define PKGCONF_CACHE_INODES
+#endif
+
+static bool
+#ifdef PKGCONF_CACHE_INODES
+path_list_contains_entry(const char *text, pkgconf_list_t *dirlist, struct stat *st)
+#else
+path_list_contains_entry(const char *text, pkgconf_list_t *dirlist)
+#endif
+{
+	pkgconf_node_t *n;
+
+	PKGCONF_FOREACH_LIST_ENTRY(dirlist->head, n)
+	{
+		pkgconf_path_t *pn = n->data;
+
+#ifdef PKGCONF_CACHE_INODES
+		if (pn->handle_device == (void *)(intptr_t)st->st_dev && pn->handle_path == (void *)(intptr_t)st->st_ino)
+			return true;
+#endif
+
+		if (!strcmp(text, pn->path))
+			return true;
+	}
+
+	return false;
+}
+
+/*
+ * !doc
+ *
+ * libpkgconf `path` module
+ * ========================
+ *
+ * The `path` module provides functions for manipulating lists of paths in a cross-platform manner.  Notably,
+ * it is used by the `pkgconf client` to parse the ``PKG_CONFIG_PATH``, ``PKG_CONFIG_LIBDIR`` and related environment
+ * variables.
+ */
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_path_add(const char *text, pkgconf_list_t *dirlist)
+ *
+ *    Adds a path node to a path list.  If the path is already in the list, do nothing.
+ *
+ *    :param char* text: The path text to add as a path node.
+ *    :param pkgconf_list_t* dirlist: The path list to add the path node to.
+ *    :param bool filter: Whether to perform duplicate filtering.
+ *    :return: nothing
+ */
+void
+pkgconf_path_add(const char *text, pkgconf_list_t *dirlist, bool filter)
+{
+	pkgconf_path_t *node;
+	char path[PKGCONF_BUFSIZE];
+
+#ifdef PKGCONF_CACHE_INODES
+	struct stat st;
+
+	if (filter)
+	{
+		if (lstat(text, &st) == -1)
+			return;
+		if (S_ISLNK(st.st_mode))
+		{
+			char linkdest[PKGCONF_BUFSIZE];
+			ssize_t len = readlink(text, linkdest, sizeof(linkdest));
+
+			if (len != -1 && (size_t)len < sizeof(linkdest) &&
+				stat(linkdest, &st) == -1)
+				return;
+		}
+		if (path_list_contains_entry(text, dirlist, &st))
+			return;
+	}
+#else
+	if (filter && path_list_contains_entry(text, dirlist))
+		return;
+#endif
+
+	pkgconf_strlcpy(path, text, sizeof path);
+	pkgconf_path_relocate(path, sizeof path);
+
+	node = calloc(sizeof(pkgconf_path_t), 1);
+	node->path = strdup(path);
+
+#ifdef PKGCONF_CACHE_INODES
+	if (filter) {
+		node->handle_path = (void *)(intptr_t) st.st_ino;
+		node->handle_device = (void *)(intptr_t) st.st_dev;
+	}
+#endif
+
+	pkgconf_node_insert_tail(&node->lnode, node, dirlist);
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: size_t pkgconf_path_split(const char *text, pkgconf_list_t *dirlist)
+ *
+ *    Splits a given text input and inserts paths into a path list.
+ *
+ *    :param char* text: The path text to split and add as path nodes.
+ *    :param pkgconf_list_t* dirlist: The path list to have the path nodes added to.
+ *    :param bool filter: Whether to perform duplicate filtering.
+ *    :return: number of path nodes added to the path list
+ *    :rtype: size_t
+ */
+size_t
+pkgconf_path_split(const char *text, pkgconf_list_t *dirlist, bool filter)
+{
+	size_t count = 0;
+	char *workbuf, *p, *iter;
+
+	if (text == NULL)
+		return 0;
+
+	iter = workbuf = strdup(text);
+	while ((p = strtok(iter, PKG_CONFIG_PATH_SEP_S)) != NULL)
+	{
+		pkgconf_path_add(p, dirlist, filter);
+
+		count++, iter = NULL;
+	}
+	free(workbuf);
+
+	return count;
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: size_t pkgconf_path_build_from_environ(const char *envvarname, const char *fallback, pkgconf_list_t *dirlist)
+ *
+ *    Adds the paths specified in an environment variable to a path list.  If the environment variable is not set,
+ *    an optional default set of paths is added.
+ *
+ *    :param char* envvarname: The environment variable to look up.
+ *    :param char* fallback: The fallback paths to use if the environment variable is not set.
+ *    :param pkgconf_list_t* dirlist: The path list to add the path nodes to.
+ *    :param bool filter: Whether to perform duplicate filtering.
+ *    :return: number of path nodes added to the path list
+ *    :rtype: size_t
+ */
+size_t
+pkgconf_path_build_from_environ(const char *envvarname, const char *fallback, pkgconf_list_t *dirlist, bool filter)
+{
+	const char *data;
+
+	data = getenv(envvarname);
+	if (data != NULL)
+		return pkgconf_path_split(data, dirlist, filter);
+
+	if (fallback != NULL)
+		return pkgconf_path_split(fallback, dirlist, filter);
+
+	/* no fallback and no environment variable, thusly no nodes added */
+	return 0;
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: bool pkgconf_path_match_list(const char *path, const pkgconf_list_t *dirlist)
+ *
+ *    Checks whether a path has a matching prefix in a path list.
+ *
+ *    :param char* path: The path to check against a path list.
+ *    :param pkgconf_list_t* dirlist: The path list to check the path against.
+ *    :return: true if the path list has a matching prefix, otherwise false
+ *    :rtype: bool
+ */
+bool
+pkgconf_path_match_list(const char *path, const pkgconf_list_t *dirlist)
+{
+	pkgconf_node_t *n = NULL;
+	char relocated[PKGCONF_BUFSIZE];
+	const char *cpath = path;
+
+	pkgconf_strlcpy(relocated, path, sizeof relocated);
+	if (pkgconf_path_relocate(relocated, sizeof relocated))
+		cpath = relocated;
+
+	PKGCONF_FOREACH_LIST_ENTRY(dirlist->head, n)
+	{
+		pkgconf_path_t *pnode = n->data;
+
+		if (!strcmp(pnode->path, cpath))
+			return true;
+	}
+
+	return false;
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_path_free(pkgconf_list_t *dirlist)
+ *
+ *    Releases any path nodes attached to the given path list.
+ *
+ *    :param pkgconf_list_t* dirlist: The path list to clean up.
+ *    :return: nothing
+ */
+void
+pkgconf_path_free(pkgconf_list_t *dirlist)
+{
+	pkgconf_node_t *n, *tn;
+
+	PKGCONF_FOREACH_LIST_ENTRY_SAFE(dirlist->head, tn, n)
+	{
+		pkgconf_path_t *pnode = n->data;
+
+		free(pnode->path);
+		free(pnode);
+	}
+}
+
+static char *
+normpath(const char *path)
+{
+	if (!path)
+		return NULL;
+
+	char *copy = strdup(path);
+	if (NULL == copy)
+		return NULL;
+	char *ptr = copy;
+
+	for (int ii = 0; copy[ii]; ii++)
+	{
+		*ptr++ = path[ii];
+		if ('/' == path[ii])
+		{
+			ii++;
+			while ('/' == path[ii])
+				ii++;
+			ii--;
+		}
+	}
+	*ptr = '\0';
+
+	return copy;
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: bool pkgconf_path_relocate(char *buf, size_t buflen)
+ *
+ *    Relocates a path, possibly calling normpath() or cygwin_conv_path() on it.
+ *
+ *    :param char* buf: The path to relocate.
+ *    :param size_t buflen: The buffer length the path is contained in.
+ *    :return: true on success, false on error
+ *    :rtype: bool
+ */
+bool
+pkgconf_path_relocate(char *buf, size_t buflen)
+{
+#if defined(HAVE_CYGWIN_CONV_PATH) && defined(__MSYS__)
+	ssize_t size;
+	char *tmpbuf, *ti;
+
+	size = cygwin_conv_path(CCP_POSIX_TO_WIN_A, buf, NULL, 0);
+	if (size < 0 || (size_t) size > buflen)
+		return false;
+
+	tmpbuf = malloc(size);
+	if (cygwin_conv_path(CCP_POSIX_TO_WIN_A, buf, tmpbuf, size))
+		return false;
+
+	pkgconf_strlcpy(buf, tmpbuf, buflen);
+	free(tmpbuf);
+
+	/* rewrite any backslash arguments for best compatibility */
+	for (ti = buf; *ti != '\0'; ti++)
+	{
+		if (*ti == '\\')
+			*ti = '/';
+	}
+#else
+	char *tmpbuf;
+
+	if ((tmpbuf = normpath(buf)) != NULL)
+	{
+		size_t tmpbuflen = strlen(tmpbuf);
+		if (tmpbuflen > buflen)
+		{
+			free(tmpbuf);
+			return false;
+		}
+
+		pkgconf_strlcpy(buf, tmpbuf, buflen);
+		free(tmpbuf);
+	}
+#endif
+
+	return true;
+}
diff --git a/libpkgconf/pkg.c b/libpkgconf/pkg.c
index 92acdb2..9056965 100644
--- a/libpkgconf/pkg.c
+++ b/libpkgconf/pkg.c
@@ -35,8 +35,7 @@
 #	define strcasecmp _stricmp
 #endif
 
-#define PKG_CONFIG_EXT		".pc"
-#define PKG_CONFIG_PATH_SZ	(65535)
+#define PKG_CONFIG_EXT ".pc"
 
 static inline bool
 str_has_suffix(const char *str, const char *suffix)
@@ -275,8 +274,7 @@ pkgconf_pkg_new_from_file(pkgconf_client_t *client, const char *filename, FILE *
 {
 	pkgconf_pkg_t *pkg;
 	char readbuf[PKGCONF_BUFSIZE];
-	char pathbuf[PKGCONF_BUFSIZE];
-	char prefixbuf[PKGCONF_BUFSIZE];
+	char pathbuf[PKGCONF_SBUFSIZE];
 	char *idptr;
 	size_t lineno = 0;
 
@@ -362,7 +360,7 @@ pkgconf_pkg_new_from_file(pkgconf_client_t *client, const char *filename, FILE *
 				pkgconf_tuple_add(client, &pkg->vars, key, value, true);
 			else
 			{
-				const char *relvalue = determine_prefix(pkg, prefixbuf, sizeof prefixbuf);
+				const char *relvalue = determine_prefix(pkg, pathbuf, sizeof pathbuf);
 				if (relvalue != NULL)
 				{
 					pkgconf_tuple_add(client, &pkg->vars, "orig_prefix", value, true);
@@ -497,8 +495,8 @@ pkgconf_pkg_try_specific_path(pkgconf_client_t *client, const char *path, const
 {
 	pkgconf_pkg_t *pkg = NULL;
 	FILE *f;
-	char locbuf[PKG_CONFIG_PATH_SZ];
-	char uninst_locbuf[PKG_CONFIG_PATH_SZ];
+	char locbuf[PKGCONF_SBUFSIZE];
+	char uninst_locbuf[PKGCONF_SBUFSIZE];
 
 	PKGCONF_TRACE(client, "trying path: %s for %s", path, name);
 
@@ -535,7 +533,7 @@ pkgconf_pkg_scan_dir(pkgconf_client_t *client, const char *path, void *data, pkg
 
 	for (dirent = readdir(dir); dirent != NULL; dirent = readdir(dir))
 	{
-		char filebuf[PKGCONF_BUFSIZE];
+		char filebuf[PKGCONF_SBUFSIZE];
 		pkgconf_pkg_t *pkg;
 		FILE *f;
 
@@ -657,7 +655,7 @@ pkgconf_pkg_find_in_registry_key(pkgconf_client_t *client, HKEY hkey, const char
 pkgconf_pkg_t *
 pkgconf_pkg_find(pkgconf_client_t *client, const char *name)
 {
-	char pathbuf[PKGCONF_BUFSIZE];
+	char pathbuf[PKGCONF_SBUFSIZE];
 	pkgconf_pkg_t *pkg = NULL;
 	pkgconf_node_t *n;
 	FILE *f;
@@ -737,7 +735,7 @@ int
 pkgconf_compare_version(const char *a, const char *b)
 {
 	char oldch1, oldch2;
-	char buf1[PKGCONF_BUFSIZE], buf2[PKGCONF_BUFSIZE];
+	char buf1[PKGCONF_SBUFSIZE], buf2[PKGCONF_SBUFSIZE];
 	char *str1, *str2;
 	char *one, *two;
 	int ret;
diff --git a/libpkgconf/stdinc.h b/libpkgconf/stdinc.h
index a4c7c84..abebe03 100644
--- a/libpkgconf/stdinc.h
+++ b/libpkgconf/stdinc.h
@@ -59,4 +59,42 @@
 # include <unistd.h>
 #endif
 
+/*
+ * Stack-allocated buffer sizes.
+ *
+ * Original libpkgconf package uses PKGCONF_BUFSIZE size for all
+ * stack-allocated buffers, imposing high requirements for the thread stack
+ * size. This make it unusable on MacOS (as of 10.12) for non-main threads that
+ * are created with the default 512K stack size. In particular that make it
+ * impossible to use libpkgconf API in threads created with C++11 std::thread
+ * class, that doesn't allow stack size customization.
+ *
+ * As an example, using pkgconf_pkg_find() for quite a simple .pc file consumes
+ * at least 460K. The measurment was made as a differece between addresses of 2
+ * stack-allocated variables: one was defined right before the function call,
+ * another right after the buffer definition in pkgconf_tuple_parse() function.
+ *
+ * To relax the stack size requirements we will minimize the usage of
+ * PKGCONF_BUFSIZE, using the smaller PKGCONF_SBUFSIZE instead, wherever it is
+ * possible. The PKGCONF_SBUFSIZE is selected in such a way that a buffer of
+ * this size can accommodate the file system path, the value fragment, the
+ * variable name or the package dependency specification. The latest implies it
+ * also fits for the package key or the package version. This optimization
+ * decreased the stack usage for the described use case to 140K.
+ *
+ * Note that we moved PKGCONF_BUFSIZE definition from libpkgconf.h.
+ */
+#define PKGCONF_BUFSIZE (65535)
+
+#ifdef _WIN32
+# define PKGCONF_SBUFSIZE (_MAX_PATH + 1024)
+#else
+# include <limits.h>
+# ifdef PATH_MAX
+#  define PKGCONF_SBUFSIZE (PATH_MAX + 1024)
+# else
+#  define PKGCONF_SBUFSIZE (4096 + 1024)
+# endif
+#endif
+
 #endif
diff --git a/libpkgconf/tuple.c b/libpkgconf/tuple.c
index b0cda45..ae5fe55 100644
--- a/libpkgconf/tuple.c
+++ b/libpkgconf/tuple.c
@@ -231,7 +231,7 @@ pkgconf_tuple_parse(const pkgconf_client_t *client, pkgconf_list_t *vars, const
 			*bptr++ = *ptr;
 		else if (*(ptr + 1) == '{')
 		{
-			char varname[PKGCONF_BUFSIZE];
+			char varname[PKGCONF_SBUFSIZE];
 			char *vptr = varname;
 			const char *pptr;
 			char *kv, *parsekv;
@@ -295,7 +295,7 @@ pkgconf_tuple_parse(const pkgconf_client_t *client, pkgconf_list_t *vars, const
 	    strlen(buf) > strlen(client->sysroot_dir) &&
 	    strstr(buf + strlen(client->sysroot_dir), client->sysroot_dir) != NULL)
 	{
-		char cleanpath[PKGCONF_BUFSIZE];
+		char cleanpath[PKGCONF_SBUFSIZE];
 
 		pkgconf_strlcpy(cleanpath, buf + strlen(client->sysroot_dir), sizeof cleanpath);
 		pkgconf_path_relocate(cleanpath, sizeof cleanpath);
diff --git a/libpkgconf/tuple.c.orig b/libpkgconf/tuple.c.orig
new file mode 100644
index 0000000..b0cda45
--- /dev/null
+++ b/libpkgconf/tuple.c.orig
@@ -0,0 +1,348 @@
+/*
+ * tuple.c
+ * management of key->value tuples
+ *
+ * Copyright (c) 2011, 2012 pkgconf authors (see AUTHORS).
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * This software is provided 'as is' and without any warranty, express or
+ * implied.  In no event shall the authors be liable for any damages arising
+ * from the use of this software.
+ */
+
+#include <libpkgconf/stdinc.h>
+#include <libpkgconf/libpkgconf.h>
+
+/*
+ * !doc
+ *
+ * libpkgconf `tuple` module
+ * =========================
+ *
+ * The `tuple` module provides key-value mappings backed by a linked list.  The key-value
+ * mapping is mainly used for variable substitution when parsing .pc files.
+ *
+ * There are two sets of mappings: a ``pkgconf_pkg_t`` specific mapping, and a `global` mapping.
+ * The `tuple` module provides convenience wrappers for managing the `global` mapping, which is
+ * attached to a given client object.
+ */
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_tuple_add_global(pkgconf_client_t *client, const char *key, const char *value)
+ *
+ *    Defines a global variable, replacing the previous declaration if one was set.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client object to modify.
+ *    :param char* key: The key for the mapping (variable name).
+ *    :param char* value: The value for the mapped entry.
+ *    :return: nothing
+ */
+void
+pkgconf_tuple_add_global(pkgconf_client_t *client, const char *key, const char *value)
+{
+	pkgconf_tuple_add(client, &client->global_vars, key, value, false);
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_tuple_find_global(const pkgconf_client_t *client, const char *key)
+ *
+ *    Looks up a global variable.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client object to access.
+ *    :param char* key: The key or variable name to look up.
+ *    :return: the contents of the variable or ``NULL``
+ *    :rtype: char *
+ */
+char *
+pkgconf_tuple_find_global(const pkgconf_client_t *client, const char *key)
+{
+	pkgconf_node_t *node;
+
+	PKGCONF_FOREACH_LIST_ENTRY(client->global_vars.head, node)
+	{
+		pkgconf_tuple_t *tuple = node->data;
+
+		if (!strcmp(tuple->key, key))
+			return tuple->value;
+	}
+
+	return NULL;
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_tuple_free_global(pkgconf_client_t *client)
+ *
+ *    Delete all global variables associated with a pkgconf client object.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client object to modify.
+ *    :return: nothing
+ */
+void
+pkgconf_tuple_free_global(pkgconf_client_t *client)
+{
+	pkgconf_tuple_free(&client->global_vars);
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_tuple_define_global(pkgconf_client_t *client, const char *kv)
+ *
+ *    Parse and define a global variable.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client object to modify.
+ *    :param char* kv: The variable in the form of ``key=value``.
+ *    :return: nothing
+ */
+void
+pkgconf_tuple_define_global(pkgconf_client_t *client, const char *kv)
+{
+	char *workbuf = strdup(kv);
+	char *value;
+
+	value = strchr(workbuf, '=');
+	if (value == NULL)
+		goto out;
+
+	*value++ = '\0';
+	pkgconf_tuple_add_global(client, workbuf, value);
+out:
+	free(workbuf);
+}
+
+static void
+pkgconf_tuple_find_delete(pkgconf_list_t *list, const char *key)
+{
+	pkgconf_node_t *node, *next;
+
+	PKGCONF_FOREACH_LIST_ENTRY_SAFE(list->head, next, node)
+	{
+		pkgconf_tuple_t *tuple = node->data;
+
+		if (!strcmp(tuple->key, key))
+		{
+			pkgconf_tuple_free_entry(tuple, list);
+			return;
+		}
+	}
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: pkgconf_tuple_t *pkgconf_tuple_add(const pkgconf_client_t *client, pkgconf_list_t *list, const char *key, const char *value, bool parse)
+ *
+ *    Optionally parse and then define a variable.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client object to access.
+ *    :param pkgconf_list_t* list: The variable list to add the new variable to.
+ *    :param char* key: The name of the variable being added.
+ *    :param char* value: The value of the variable being added.
+ *    :param bool parse: Whether or not to parse the value for variable substitution.
+ *    :return: a variable object
+ *    :rtype: pkgconf_tuple_t *
+ */
+pkgconf_tuple_t *
+pkgconf_tuple_add(const pkgconf_client_t *client, pkgconf_list_t *list, const char *key, const char *value, bool parse)
+{
+	pkgconf_tuple_t *tuple = calloc(sizeof(pkgconf_tuple_t), 1);
+
+	pkgconf_tuple_find_delete(list, key);
+
+	tuple->key = strdup(key);
+	if (parse)
+		tuple->value = pkgconf_tuple_parse(client, list, value);
+	else
+		tuple->value = strdup(value);
+
+	pkgconf_node_insert(&tuple->iter, tuple, list);
+
+	return tuple;
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: char *pkgconf_tuple_find(const pkgconf_client_t *client, pkgconf_list_t *list, const char *key)
+ *
+ *    Look up a variable in a variable list.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client object to access.
+ *    :param pkgconf_list_t* list: The variable list to search.
+ *    :param char* key: The variable name to search for.
+ *    :return: the value of the variable or ``NULL``
+ *    :rtype: char *
+ */
+char *
+pkgconf_tuple_find(const pkgconf_client_t *client, pkgconf_list_t *list, const char *key)
+{
+	pkgconf_node_t *node;
+	char *res;
+
+	if ((res = pkgconf_tuple_find_global(client, key)) != NULL)
+		return res;
+
+	PKGCONF_FOREACH_LIST_ENTRY(list->head, node)
+	{
+		pkgconf_tuple_t *tuple = node->data;
+
+		if (!strcmp(tuple->key, key))
+			return tuple->value;
+	}
+
+	return NULL;
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: char *pkgconf_tuple_parse(const pkgconf_client_t *client, pkgconf_list_t *vars, const char *value)
+ *
+ *    Parse an expression for variable substitution.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client object to access.
+ *    :param pkgconf_list_t* list: The variable list to search for variables (along side the global variable list).
+ *    :param char* value: The ``key=value`` string to parse.
+ *    :return: the variable data with any variables substituted
+ *    :rtype: char *
+ */
+char *
+pkgconf_tuple_parse(const pkgconf_client_t *client, pkgconf_list_t *vars, const char *value)
+{
+	char buf[PKGCONF_BUFSIZE];
+	const char *ptr;
+	char *bptr = buf;
+
+	if (*value == '/' && client->sysroot_dir != NULL && strncmp(value, client->sysroot_dir, strlen(client->sysroot_dir)))
+		bptr += pkgconf_strlcpy(buf, client->sysroot_dir, sizeof buf);
+
+	for (ptr = value; *ptr != '\0' && bptr - buf < PKGCONF_BUFSIZE; ptr++)
+	{
+		if (*ptr != '$' || (*ptr == '$' && *(ptr + 1) != '{'))
+			*bptr++ = *ptr;
+		else if (*(ptr + 1) == '{')
+		{
+			char varname[PKGCONF_BUFSIZE];
+			char *vptr = varname;
+			const char *pptr;
+			char *kv, *parsekv;
+
+			*vptr = '\0';
+
+			for (pptr = ptr + 2; *pptr != '\0'; pptr++)
+			{
+				if (*pptr != '}')
+					*vptr++ = *pptr;
+				else
+				{
+					*vptr = '\0';
+					break;
+				}
+			}
+
+			ptr += (pptr - ptr);
+			kv = pkgconf_tuple_find_global(client, varname);
+			if (kv != NULL)
+			{
+				strncpy(bptr, kv, PKGCONF_BUFSIZE - (bptr - buf));
+				bptr += strlen(kv);
+			}
+			else
+			{
+				kv = pkgconf_tuple_find(client, vars, varname);
+
+				if (kv != NULL)
+				{
+					parsekv = pkgconf_tuple_parse(client, vars, kv);
+
+					strncpy(bptr, parsekv, PKGCONF_BUFSIZE - (bptr - buf));
+					bptr += strlen(parsekv);
+
+					free(parsekv);
+				}
+			}
+		}
+	}
+
+	*bptr = '\0';
+
+	/*
+	 * Sigh.  Somebody actually attempted to use freedesktop.org pkg-config's broken sysroot support,
+	 * which was written by somebody who did not understand how sysroots are supposed to work.  This
+	 * results in an incorrect path being built as the sysroot will be prepended twice, once explicitly,
+	 * and once by variable expansion (the pkgconf approach).  We could simply make ${pc_sysrootdir} blank,
+	 * but sometimes it is necessary to know the explicit sysroot path for other reasons, so we can't really
+	 * do that.
+	 *
+	 * As a result, we check to see if ${pc_sysrootdir} is prepended as a duplicate, and if so, remove the
+	 * prepend.  This allows us to handle both our approach and the broken freedesktop.org implementation's
+	 * approach.  Because a path can be shorter than ${pc_sysrootdir}, we do some checks first to ensure it's
+	 * safe to skip ahead in the string to scan for our sysroot dir.
+	 *
+	 * Finally, we call pkgconf_path_relocate() to clean the path of spurious elements.
+	 */
+	if (*buf == '/' &&
+	    client->sysroot_dir != NULL &&
+	    strlen(buf) > strlen(client->sysroot_dir) &&
+	    strstr(buf + strlen(client->sysroot_dir), client->sysroot_dir) != NULL)
+	{
+		char cleanpath[PKGCONF_BUFSIZE];
+
+		pkgconf_strlcpy(cleanpath, buf + strlen(client->sysroot_dir), sizeof cleanpath);
+		pkgconf_path_relocate(cleanpath, sizeof cleanpath);
+
+		return strdup(cleanpath);
+	}
+
+	return strdup(buf);
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_tuple_free_entry(pkgconf_tuple_t *tuple, pkgconf_list_t *list)
+ *
+ *    Deletes a variable object, removing it from any variable lists and releasing any memory associated
+ *    with it.
+ *
+ *    :param pkgconf_tuple_t* tuple: The variable object to release.
+ *    :param pkgconf_list_t* list: The variable list the variable object is attached to.
+ *    :return: nothing
+ */
+void
+pkgconf_tuple_free_entry(pkgconf_tuple_t *tuple, pkgconf_list_t *list)
+{
+	pkgconf_node_delete(&tuple->iter, list);
+
+	free(tuple->key);
+	free(tuple->value);
+	free(tuple);
+}
+
+/*
+ * !doc
+ *
+ * .. c:function:: void pkgconf_tuple_free(pkgconf_list_t *list)
+ *
+ *    Deletes a variable list and any variables attached to it.
+ *
+ *    :param pkgconf_list_t* list: The variable list to delete.
+ *    :return: nothing
+ */
+void
+pkgconf_tuple_free(pkgconf_list_t *list)
+{
+	pkgconf_node_t *node, *next;
+
+	PKGCONF_FOREACH_LIST_ENTRY_SAFE(list->head, next, node)
+		pkgconf_tuple_free_entry(node->data, list);
+}