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-rw-r--r--libbutl/command.cxx269
-rw-r--r--libbutl/command.mxx84
-rw-r--r--tests/command/buildfile8
-rw-r--r--tests/command/driver.cxx255
-rw-r--r--tests/command/testscript155
5 files changed, 771 insertions, 0 deletions
diff --git a/libbutl/command.cxx b/libbutl/command.cxx
new file mode 100644
index 0000000..89d7c68
--- /dev/null
+++ b/libbutl/command.cxx
@@ -0,0 +1,269 @@
+// file : libbutl/command.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license : MIT; see accompanying LICENSE file
+
+#ifndef __cpp_modules
+#include <libbutl/command.mxx>
+#endif
+
+#include <cassert>
+
+#ifndef __cpp_lib_modules
+#include <map>
+#include <string>
+#include <cstddef>
+#include <functional>
+
+#include <ios> // ios::failure
+#include <vector>
+#include <utility> // move()
+#include <stdexcept> // invalid_argument
+#endif
+
+// Other includes.
+
+#ifdef __cpp_modules
+module butl.command;
+
+// Only imports additional to interface.
+#ifdef __clang__
+#ifdef __cpp_lib_modules
+import std.core;
+import std.io;
+#endif
+import butl.process;
+import butl.optional;
+#endif
+
+import butl.fdstream;
+import butl.string_parser;
+#else
+#include <libbutl/fdstream.mxx>
+#include <libbutl/string-parser.mxx>
+#endif
+
+using namespace std;
+
+namespace butl
+{
+ process_exit
+ command_run (const string& cmd_str,
+ const optional<process_env>& env,
+ const optional<command_substitution_map>& substitutions,
+ char subst,
+ const function<command_callback>& callback)
+ {
+ // Split the command line into the program path, arguments, and redirects,
+ // removing one level of quoting.
+ //
+ // Note: may throw invalid_argument.
+ //
+ vector<string> cmd (
+ string_parser::parse_quoted (cmd_str, true /* unquote */));
+
+ auto bad_arg = [] (const string& d) {throw invalid_argument (d);};
+
+ if (cmd.empty ())
+ bad_arg ("no program path specified");
+
+ // Perform substitutions in a string. Throw invalid_argument for a
+ // malformed substitution or an unknown variable.
+ //
+ auto substitute = [&substitutions, subst, &bad_arg] (string&& s)
+ {
+ if (!substitutions)
+ return move (s);
+
+ string r;
+ size_t p (0); // Current parsing position.
+
+ for (size_t sp; (sp = s.find (subst, p)) != string::npos; ++p)
+ {
+ // Append the source string fraction preceding this substitution.
+ //
+ r.append (s, p, sp - p);
+
+ ++sp; // Start of the variable name.
+ p = s.find (subst, sp); // End of the variable name.
+
+ // Unescape the substitution character (adjacent substitution
+ // characters).
+ //
+ if (p == sp)
+ {
+ r += subst;
+ continue;
+ }
+
+ // Verify that the variable name is properly terminated and doesn't
+ // contain whitespaces.
+ //
+ if (p == string::npos)
+ bad_arg (string ("unmatched substitution character '") + subst +
+ "' in '" + s + "'");
+
+ string vn (s, sp, p - sp);
+
+ assert (!vn.empty ()); // Otherwise it would be an escape sequence.
+
+ if (vn.find_first_of (" \t") != string::npos)
+ bad_arg ("whitespace in variable name '" + vn + "'");
+
+ // Find the variable and append its value or fail if it's unknown.
+ //
+ auto i (substitutions->find (vn));
+
+ if (i == substitutions->end ())
+ bad_arg ("unknown variable '" + vn + "'");
+
+ r += i->second;
+ }
+
+ // Append the source string tail, following the last substitution, and
+ // optimizing for the no-substitutions case.
+ //
+ if (p == 0)
+ return move (s);
+
+ r.append (s.begin () + p, s.end ());
+ return r;
+ };
+
+ // Perform substitutions in the program path.
+ //
+ string prog (substitute (move (cmd.front ())));
+
+ // Sort the remaining command line elements into the arguments and
+ // redirects, performing the substitutions. Complete relative redirects
+ // against CWD and use the rightmost redirect.
+ //
+ vector<string> args;
+
+ optional<dir_path> redir;
+ bool redir_append (false);
+
+ const dir_path& cwd (env && env->cwd != nullptr ? *env->cwd : dir_path ());
+
+ for (auto i (cmd.begin () + 1), e (cmd.end ()); i != e; ++i)
+ {
+ string a (move (*i));
+
+ if (a[0] == '>') // Redirect.
+ {
+ redir_append = a[1] == '>';
+
+ size_t n (redir_append ? 2 : 1);
+
+ if (a.size () != n) // Strip the >/>> prefix.
+ {
+ a.erase (0, n);
+ }
+ else // Take the space-separated file path from the next element.
+ {
+ if (++i == e)
+ bad_arg ("no stdout redirect file specified");
+
+ a = move (*i);
+ }
+
+ try
+ {
+ redir = dir_path (substitute (move (a)));
+ }
+ catch (const invalid_path& e)
+ {
+ bad_arg ("invalid stdout redirect file path '" + e.path + "'");
+ }
+
+ if (redir->empty ())
+ bad_arg ("empty stdout redirect file path");
+
+ if (redir->relative () && !cwd.empty ())
+ redir = cwd / *redir;
+ }
+ else // Argument.
+ {
+ args.push_back (substitute (move (a)));
+ }
+ }
+
+ // Prepare the process environment.
+ //
+ // Note: cwd passed to process_env() may not be a temporary object.
+ //
+ process_env pe (prog, cwd, env ? env->vars : nullptr);
+
+ // Open the redirect file descriptor, if specified.
+ //
+ // Intercept the exception to make the error description more informative.
+ //
+ auto_fd rd;
+
+ if (redir)
+ try
+ {
+ fdopen_mode m (fdopen_mode::out | fdopen_mode::create);
+ m |= redir_append ? fdopen_mode::at_end : fdopen_mode::truncate;
+
+ rd = fdopen (*redir, m);
+ }
+ catch (const ios::failure& e)
+ {
+ // @@ For libstdc++ the resulting exception description will be
+ // something like:
+ //
+ // unable to open stdout redirect file ...: No such file or directory
+ //
+ // Maybe we should improve our operator<<(ostream,exception) to
+ // lowercase the first word that follows ": " (code description) for
+ // exceptions derived from system_error.
+ //
+ string msg ("unable to open stdout redirect file '" + redir->string () +
+ "'");
+
+ // For old versions of g++ (as of 4.9) ios_base::failure is not derived
+ // from system_error and so we cannot recover the errno value. Lets use
+ // EIO in this case. This is a temporary code after all.
+ //
+ const system_error* se (dynamic_cast<const system_error*> (&e));
+
+ throw_generic_ios_failure (se != nullptr ? se->code ().value () : EIO,
+ msg.c_str ());
+ }
+
+ // Finally, run the process.
+ //
+ // If the callback is specified, then intercept its call, appending the
+ // stdout redirect to the arguments list, if present.
+ //
+ return process_run_callback (
+ [&callback, &redir, redir_append] (const char* const args[], size_t n)
+ {
+ if (callback)
+ {
+ if (redir)
+ {
+ vector<const char*> elems (args, args + n);
+ string rd ((redir_append ? ">>" : ">") + redir->string ());
+
+ // Inject the redirect prior to the trailing NULL.
+ //
+ assert (n > 0);
+
+ elems.insert (elems.begin () + n - 1, rd.c_str ());
+
+ callback (elems.data (), elems.size ());
+ }
+ else
+ {
+ callback (args, n);
+ }
+ }
+ },
+ 0 /* stdin */,
+ redir ? rd.get () : 1 /* stdout */,
+ 2 /* stderr */,
+ pe,
+ args);
+ }
+}
diff --git a/libbutl/command.mxx b/libbutl/command.mxx
new file mode 100644
index 0000000..e62a032
--- /dev/null
+++ b/libbutl/command.mxx
@@ -0,0 +1,84 @@
+// file : libbutl/command.mxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license : MIT; see accompanying LICENSE file
+
+#ifndef __cpp_modules
+#pragma once
+#endif
+
+#ifndef __cpp_lib_modules
+#include <map>
+#include <string>
+#include <cstddef> // size_t
+#include <functional>
+#endif
+
+// Other includes.
+
+#ifdef __cpp_modules
+export module butl.command;
+#ifdef __cpp_lib_modules
+import std.core;
+#endif
+import butl.process;
+import butl.optional;
+#else
+#include <libbutl/process.mxx>
+#include <libbutl/optional.mxx>
+#endif
+
+#include <libbutl/export.hxx>
+
+LIBBUTL_MODEXPORT namespace butl
+{
+ // Run a process, interpreting the command line as whitespace-separated,
+ // potentially quoted program path, arguments, and redirects. Throw
+ // std::invalid_argument on the parsing error, ios::failure on the
+ // underlying OS error, and process_error on the process running error.
+ //
+ // The process environment path is unused and must point to the empty
+ // process path.
+ //
+ // Currently only the following stdout redirects are supported:
+ //
+ // >file # Overwrite file.
+ // >>file # Append to file.
+ //
+ // In particular, the file descriptor cannot be specified. The file path can
+ // optionally be separated from '>' by whitespaces. Note that redirects are
+ // distinguished from arguments by the presence of leading '>' and prior to
+ // possible substitutions (so the redirect character cannot be the result of
+ // a substitution; see below).
+ //
+ // The relative redirect file paths are completed against the command
+ // current working directory. Note that if it is altered via the process
+ // environment, then the new value is used.
+ //
+ // The command line elements (program, arguments, etc) may optionally
+ // contain substitutions - variable names enclosed with the substitution
+ // symbol ('@' by default) - which are replaced with the corresponding
+ // variable values to produce the actual command. Variable names must not
+ // contain whitespaces and an attempt to substitute an unknown or a
+ // malformed variable is an error. Double substitution character ('@@' by
+ // default) is an escape sequence.
+ //
+ // If the variable map is absent, then '@' has no special meaning and is
+ // treated as a regular character.
+ //
+ // The callback function, if specified, is called prior to running the
+ // command process with the substituted command elements and including
+ // redirects which will be in the "canonical" form (single argument without
+ // space after '>'). The callback can be used, for example, for tracing the
+ // resulting command line, etc.
+ //
+ using command_substitution_map = std::map<std::string, std::string>;
+ using command_callback = void (const char* const args[], std::size_t n);
+
+ LIBBUTL_SYMEXPORT process_exit
+ command_run (const std::string& command,
+ const optional<process_env>& = nullopt,
+ const optional<command_substitution_map>& = nullopt,
+ char subst = '@',
+ const std::function<command_callback>& = {});
+
+}
diff --git a/tests/command/buildfile b/tests/command/buildfile
new file mode 100644
index 0000000..cb0f272
--- /dev/null
+++ b/tests/command/buildfile
@@ -0,0 +1,8 @@
+# file : tests/command/buildfile
+# copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+# license : MIT; see accompanying LICENSE file
+
+import libs = libbutl%lib{butl}
+libs += $stdmod_lib
+
+exe{driver}: {hxx cxx}{*} $libs testscript
diff --git a/tests/command/driver.cxx b/tests/command/driver.cxx
new file mode 100644
index 0000000..a1baf68
--- /dev/null
+++ b/tests/command/driver.cxx
@@ -0,0 +1,255 @@
+// file : tests/command/driver.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license : MIT; see accompanying LICENSE file
+
+#include <cassert>
+
+#ifndef __cpp_lib_modules
+#include <ios>
+#include <string>
+#include <vector>
+#include <iostream>
+#include <stdexcept> // invalid_argument
+#endif
+
+// Other includes.
+
+#ifdef __cpp_modules
+#ifdef __cpp_lib_modules
+import std.core;
+import std.io;
+#endif
+import butl.path;
+import butl.path_io;
+import butl.process; // process::print()
+import butl.command;
+import butl.utility;
+import butl.optional;
+#else
+#include <libbutl/path.mxx>
+#include <libbutl/path-io.mxx>
+#include <libbutl/process.mxx>
+#include <libbutl/command.mxx>
+#include <libbutl/utility.mxx>
+#include <libbutl/optional.mxx>
+#endif
+
+using namespace std;
+using namespace butl;
+
+// Usages:
+//
+// argv[0] [-d <dir>] [-v <name>[=<value>]] [-s <name>=<value>] [-c <char>]
+// [-p] <command>
+//
+// argv[0] -C [-A] [-D] [-V <name>] [-S <status>] <arguments>
+//
+// In the first form run the specified command, changing the current
+// directory, (re)setting the environment variables, performing substitutions,
+// and printing the "expanded" command line, if requested.
+//
+// In the second form optionally print the program arguments, CWD, the
+// environment variable values and exit with the status specified. This mode
+// is normally used for the command being tested to dump the environment
+// obtained from the caller.
+//
+// -d <dir>
+// Change the CWD for the command process.
+//
+// -v <name>[=<value>]
+// (Un)set the environment variable for the command process. Can be
+// specified multiple times.
+//
+// -s <name>=<value>
+// Perform command line substitutions using the specified variable. Can be
+// specified multiple times.
+//
+// -c <char>
+// Substitution symbol. The default is '@'.
+//
+// -p
+// Print the "expanded" command line.
+//
+// -C
+// Print the program arguments (-A), CWD (-D), environment variables (-V)
+// to stdout and exit with the status specifies (-S).
+//
+// -A
+// Print the program arguments to stdout.
+//
+// -D
+// Print the process CWD to stdout.
+//
+// -V <name>
+// Print the environment variable value (or <unset>) to stdout. Can be
+// specified multiple times.
+//
+// -S <status>
+// Exit with the specified status code.
+//
+int
+main (int argc, const char* argv[])
+{
+ using butl::optional;
+ using butl::getenv;
+
+ // Parse and validate the arguments.
+ //
+ dir_path cwd;
+ vector<const char*> vars;
+ optional<command_substitution_map> substitutions;
+ char subst ('@');
+ optional<string> command;
+ bool print (false);
+
+ for (int i (1); i != argc; ++i)
+ {
+ string o (argv[i]);
+
+ if (o == "-d")
+ {
+ assert (++i != argc);
+ cwd = dir_path (argv[i]);
+ }
+ else if (o == "-v")
+ {
+ assert (++i != argc);
+ vars.push_back (argv[i]);
+ }
+ else if (o == "-s")
+ {
+ assert (++i != argc);
+
+ if (!substitutions)
+ substitutions = command_substitution_map ();
+
+ string v (argv[i]);
+ size_t p (v.find ('='));
+
+ assert (p != string::npos && p != 0);
+
+ (*substitutions)[string (v, 0, p)] = string (v, p + 1);
+ }
+ else if (o == "-c")
+ {
+ assert (++i != argc);
+
+ string v (argv[i]);
+
+ assert (v.size () == 1);
+ subst = v[0];
+ }
+ else if (o == "-p")
+ {
+ print = true;
+ }
+ else if (o == "-C")
+ {
+ assert (i == 1); // Must go first.
+
+ int ec (0);
+ bool print_cwd (false);
+
+ // Include the program path into the arguments list.
+ //
+ vector<const char*> args ({argv[0]});
+
+ for (++i; i != argc; ++i)
+ {
+ o = argv[i];
+
+ if (o == "-A")
+ {
+ print = true;
+ }
+ else if (o == "-D")
+ {
+ print_cwd = true;
+ }
+ else if (o == "-V")
+ {
+ assert (++i != argc);
+ vars.push_back (argv[i]);
+ }
+ else if (o == "-S")
+ {
+ assert (++i != argc);
+ ec = stoi (argv[i]);
+ }
+ else
+ args.push_back (argv[i]);
+ }
+
+ args.push_back (nullptr);
+
+ if (print)
+ {
+ process::print (cout, args.data ());
+ cout << endl;
+ }
+
+ if (print_cwd)
+ cout << dir_path::current_directory () << endl;
+
+ for (const auto& v: vars)
+ {
+ optional<string> vv (getenv (v));
+ cout << (vv ? *vv : "<unset>") << endl;
+ }
+
+ return ec;
+ }
+ else
+ {
+ assert (!command);
+ command = argv[i];
+ }
+ }
+
+ assert (command);
+
+ // Run the command.
+ //
+ try
+ {
+ optional<process_env> pe;
+
+ if (!cwd.empty () || !vars.empty ())
+ pe = process_env (process_path (), cwd, vars);
+
+ process_exit e (command_run (*command,
+ pe,
+ substitutions,
+ subst,
+ [print] (const char* const args[], size_t n)
+ {
+ if (print)
+ {
+ process::print (cout, args, n);
+ cout << endl;
+ }
+ }));
+
+ if (!e)
+ cerr << "process " << argv[0] << " " << e << endl;
+
+ return e.normal () ? e.code () : 1;
+ }
+ catch (const invalid_argument& e)
+ {
+ cerr << e << endl;
+ return 1;
+ }
+ catch (const ios::failure& e)
+ {
+ cerr << e << endl;
+ return 1;
+ }
+ catch (const process_error& e)
+ {
+ cerr << e << endl;
+ return 1;
+ }
+
+ return 0;
+}
diff --git a/tests/command/testscript b/tests/command/testscript
new file mode 100644
index 0000000..4d45f4f
--- /dev/null
+++ b/tests/command/testscript
@@ -0,0 +1,155 @@
+# file : tests/command/testscript
+# copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+# license : MIT; see accompanying LICENSE file
+
+cmd="'$0' -C -A" # Command that prints its arguments to stdout.
+
+# Note that when cross-testing the driver may not be able to run the command
+# due to the meaningless program path.
+#
++if ($test.target != $build.host)
+ exit
+end
+
+: quioting
+:
+{
+ $* "$cmd 'abc def'" >~'%.+ "abc def"%'
+}
+
+: substitution
+:
+{
+ test.options += -s v1=abc -s v2=def
+
+ : program
+ :
+ {
+ $* -s "program=$0" '@program@ -C -A abc' >~'%.+driver.* abc%'
+ }
+
+ : args
+ :
+ {
+ $* "$cmd abc" >~'%.+ abc%' : none
+ $* "$cmd x@v1@" >~'%.+ xabc%' : single
+ $* "$cmd x@v1@y@v2@z" >~'%.+ xabcydefz%' : multiple
+ $* "$cmd @v1@@v2@" >~'%.+ abcdef%' : adjacent
+ }
+
+ : redirect
+ :
+ {
+ $* -s v=f "$cmd abc >@v@" &f;
+ cat f >~'%.+ abc%'
+ }
+}
+
+: redirect
+:
+{
+ : overwrite
+ :
+ {
+ $* -p "$cmd abc >f" >~'%.+driver.* -C -A abc >f%' &f;
+ cat f >~'%.+ abc%'
+ }
+
+ : append
+ :
+ {
+ echo 'xyz' >=f;
+ $* -p "$cmd abc >>f" >~'%.+driver.* -C -A abc >>f%';
+
+ cat f >>~%EOO%
+ xyz
+ %.+ abc%
+ EOO
+ }
+
+ : space-separated
+ :
+ {
+ : overwrite
+ :
+ {
+ $* "$cmd abc > f" &f;
+ cat f >~'%.+ abc%'
+ }
+
+ : append
+ :
+ {
+ echo 'xyz' >=f;
+ $* "$cmd abc >> f";
+
+ cat f >>~%EOO%
+ xyz
+ %.+ abc%
+ EOO
+ }
+ }
+
+ : not-redirect
+ :
+ $* -s v='>f' "$cmd abc @v@" >~'%.+ abc >f%'
+
+ : errors
+ :
+ {
+ $* "$cmd >d/f" 2>~"%unable to open stdout redirect file 'd/f'.*%" != 0 : io-failure
+ $* "$cmd > ''" 2> 'empty stdout redirect file path' != 0 : empty-path
+ }
+}
+
+: invalid-argument
+:
+{
+ $* "" 2>'no program path specified' != 0 : no-prog
+ $* "p 'abc def" 2>'unterminated quoted string' != 0 : unterminated
+ $* "p >" 2>'no stdout redirect file specified' != 0 : no-redirect-file
+ $* "p >>" 2>'no stdout redirect file specified' != 0 : no-append-file
+
+ : substitution
+ :
+ {
+ test.options += -s v=a
+
+ $* 'p @a b@' 2>"unmatched substitution character '@' in '@a'" != 0 : unterm-var
+ $* "p '@a b@'" 2>"whitespace in variable name 'a b'" != 0 : ws-var
+ $* 'p @x@' 2>"unknown variable 'x'" != 0 : unknown-var
+ }
+}
+
+: process
+:
+{
+ : cwd
+ :
+ {
+ mkdir abc;
+ $* -d abc "$cmd -D" >>/~%EOO%
+ %.+/driver.*%
+ %.+/abc%
+ EOO
+ }
+
+ : env-var
+ :
+ {
+ $* -v test=abc "$cmd -V test" >>/~%EOO%
+ %.+/driver.*%
+ abc
+ EOO
+ }
+
+ : error
+ :
+ {
+ $* "''" 2>'no such file or directory' != 0 : empty-prog
+ }
+
+ : non-zero-status
+ :
+ $* "$0 -C -S 10" 2>/~'%.+ exited with code 10%' == 10
+}