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-rw-r--r--libpq/thread.c146
1 files changed, 0 insertions, 146 deletions
diff --git a/libpq/thread.c b/libpq/thread.c
deleted file mode 100644
index ed908ba..0000000
--- a/libpq/thread.c
+++ /dev/null
@@ -1,146 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * thread.c
- *
- * Prototypes and macros around system calls, used to help make
- * threaded libraries reentrant and safe to use from threaded applications.
- *
- * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group
- *
- * src/port/thread.c
- *
- *-------------------------------------------------------------------------
- */
-
-#include "c.h"
-
-#include <pwd.h>
-
-
-/*
- * Threading sometimes requires specially-named versions of functions
- * that return data in static buffers, like strerror_r() instead of
- * strerror(). Other operating systems use pthread_setspecific()
- * and pthread_getspecific() internally to allow standard library
- * functions to return static data to threaded applications. And some
- * operating systems have neither.
- *
- * Additional confusion exists because many operating systems that
- * use pthread_setspecific/pthread_getspecific() also have *_r versions
- * of standard library functions for compatibility with operating systems
- * that require them. However, internally, these *_r functions merely
- * call the thread-safe standard library functions.
- *
- * For example, BSD/OS 4.3 uses Bind 8.2.3 for getpwuid(). Internally,
- * getpwuid() calls pthread_setspecific/pthread_getspecific() to return
- * static data to the caller in a thread-safe manner. However, BSD/OS
- * also has getpwuid_r(), which merely calls getpwuid() and shifts
- * around the arguments to match the getpwuid_r() function declaration.
- * Therefore, while BSD/OS has getpwuid_r(), it isn't required. It also
- * doesn't have strerror_r(), so we can't fall back to only using *_r
- * functions for threaded programs.
- *
- * The current setup is to try threading in this order:
- *
- * use *_r function names if they exit
- * (*_THREADSAFE=yes)
- * use non-*_r functions if they are thread-safe
- *
- * One thread-safe solution for gethostbyname() might be to use getaddrinfo().
- *
- * Run src/test/thread to test if your operating system has thread-safe
- * non-*_r functions.
- */
-
-
-/*
- * Wrapper around strerror and strerror_r to use the former if it is
- * available and also return a more useful value (the error string).
- */
-char *
-pqStrerror(int errnum, char *strerrbuf, size_t buflen)
-{
-#if defined(FRONTEND) && defined(ENABLE_THREAD_SAFETY) && defined(HAVE_STRERROR_R)
- /* reentrant strerror_r is available */
-#ifdef STRERROR_R_INT
- /* SUSv3 version */
- if (strerror_r(errnum, strerrbuf, buflen) == 0)
- return strerrbuf;
- else
- return "Unknown error";
-#else
- /* GNU libc */
- return strerror_r(errnum, strerrbuf, buflen);
-#endif
-#else
- /* no strerror_r() available, just use strerror */
- strlcpy(strerrbuf, strerror(errnum), buflen);
-
- return strerrbuf;
-#endif
-}
-
-/*
- * Wrapper around getpwuid() or getpwuid_r() to mimic POSIX getpwuid_r()
- * behaviour, if that function is not available or required.
- *
- * Per POSIX, the possible cases are:
- * success: returns zero, *result is non-NULL
- * uid not found: returns zero, *result is NULL
- * error during lookup: returns an errno code, *result is NULL
- * (caller should *not* assume that the errno variable is set)
- */
-#ifndef WIN32
-int
-pqGetpwuid(uid_t uid, struct passwd * resultbuf, char *buffer,
- size_t buflen, struct passwd ** result)
-{
-#if defined(FRONTEND) && defined(ENABLE_THREAD_SAFETY) && defined(HAVE_GETPWUID_R)
- return getpwuid_r(uid, resultbuf, buffer, buflen, result);
-#else
- /* no getpwuid_r() available, just use getpwuid() */
- errno = 0;
- *result = getpwuid(uid);
- /* paranoia: ensure we return zero on success */
- return (*result == NULL) ? errno : 0;
-#endif
-}
-#endif
-
-/*
- * Wrapper around gethostbyname() or gethostbyname_r() to mimic
- * POSIX gethostbyname_r() behaviour, if it is not available or required.
- * This function is called _only_ by our getaddinfo() portability function.
- */
-#ifndef HAVE_GETADDRINFO
-int
-pqGethostbyname(const char *name,
- struct hostent * resultbuf,
- char *buffer, size_t buflen,
- struct hostent ** result,
- int *herrno)
-{
-#if defined(FRONTEND) && defined(ENABLE_THREAD_SAFETY) && defined(HAVE_GETHOSTBYNAME_R)
-
- /*
- * broken (well early POSIX draft) gethostbyname_r() which returns 'struct
- * hostent *'
- */
- *result = gethostbyname_r(name, resultbuf, buffer, buflen, herrno);
- return (*result == NULL) ? -1 : 0;
-#else
-
- /* no gethostbyname_r(), just use gethostbyname() */
- *result = gethostbyname(name);
-
- if (*result != NULL)
- *herrno = h_errno;
-
- if (*result != NULL)
- return 0;
- else
- return -1;
-#endif
-}
-
-#endif