diff options
Diffstat (limited to 'src/port/strerror.c')
| -rw-r--r-- | src/port/strerror.c | 85 |
1 files changed, 61 insertions, 24 deletions
diff --git a/src/port/strerror.c b/src/port/strerror.c index ca6910d2e6c..ba93815c50a 100644 --- a/src/port/strerror.c +++ b/src/port/strerror.c @@ -1,7 +1,7 @@ /*------------------------------------------------------------------------- * * strerror.c - * Replacement for standard strerror() function + * Replacements for standard strerror() and strerror_r() functions * * Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California @@ -15,13 +15,16 @@ #include "c.h" /* - * Within this file, "strerror" means the platform's function not pg_strerror + * Within this file, "strerror" means the platform's function not pg_strerror, + * and likewise for "strerror_r" */ #undef strerror +#undef strerror_r +static char *gnuish_strerror_r(int errnum, char *buf, size_t buflen); static char *get_errno_symbol(int errnum); #ifdef WIN32 -static char *win32_socket_strerror(int errnum); +static char *win32_socket_strerror(int errnum, char *buf, size_t buflen); #endif @@ -31,19 +34,28 @@ static char *win32_socket_strerror(int errnum); char * pg_strerror(int errnum) { - /* this buffer is only used if strerror() and get_errno_symbol() fail */ - static char errorstr_buf[48]; + static char errorstr_buf[PG_STRERROR_R_BUFLEN]; + + return pg_strerror_r(errnum, errorstr_buf, sizeof(errorstr_buf)); +} + +/* + * A slightly cleaned-up version of strerror_r() + */ +char * +pg_strerror_r(int errnum, char *buf, size_t buflen) +{ char *str; /* If it's a Windows Winsock error, that needs special handling */ #ifdef WIN32 /* Winsock error code range, per WinError.h */ if (errnum >= 10000 && errnum <= 11999) - return win32_socket_strerror(errnum); + return win32_socket_strerror(errnum, buf, buflen); #endif - /* Try the platform's strerror() */ - str = strerror(errnum); + /* Try the platform's strerror_r(), or maybe just strerror() */ + str = gnuish_strerror_r(errnum, buf, buflen); /* * Some strerror()s return an empty string for out-of-range errno. This @@ -57,18 +69,43 @@ pg_strerror(int errnum) if (str == NULL) { - snprintf(errorstr_buf, sizeof(errorstr_buf), - /*------ - translator: This string will be truncated at 47 - characters expanded. */ - _("operating system error %d"), errnum); - str = errorstr_buf; + snprintf(buf, buflen, _("operating system error %d"), errnum); + str = buf; } return str; } /* + * Simple wrapper to emulate GNU strerror_r if what the platform provides is + * POSIX. Also, if platform lacks strerror_r altogether, fall back to plain + * strerror; it might not be very thread-safe, but tough luck. + */ +static char * +gnuish_strerror_r(int errnum, char *buf, size_t buflen) +{ +#ifdef HAVE_STRERROR_R +#ifdef STRERROR_R_INT + /* POSIX API */ + if (strerror_r(errnum, buf, buflen) == 0) + return buf; + return NULL; /* let caller deal with failure */ +#else + /* GNU API */ + return strerror_r(errnum, buf, buflen); +#endif +#else /* !HAVE_STRERROR_R */ + char *sbuf = strerror(errnum); + + if (sbuf == NULL) /* can this still happen anywhere? */ + return NULL; + /* To minimize thread-unsafety hazard, copy into caller's buffer */ + strlcpy(buf, sbuf, buflen); + return buf; +#endif +} + +/* * Returns a symbol (e.g. "ENOENT") for an errno code. * Returns NULL if the code is unrecognized. */ @@ -247,9 +284,8 @@ get_errno_symbol(int errnum) * Windows' strerror() doesn't know the Winsock codes, so handle them this way */ static char * -win32_socket_strerror(int errnum) +win32_socket_strerror(int errnum, char *buf, size_t buflen) { - static char wserrbuf[256]; static HANDLE handleDLL = INVALID_HANDLE_VALUE; if (handleDLL == INVALID_HANDLE_VALUE) @@ -258,28 +294,29 @@ win32_socket_strerror(int errnum) DONT_RESOLVE_DLL_REFERENCES | LOAD_LIBRARY_AS_DATAFILE); if (handleDLL == NULL) { - sprintf(wserrbuf, "winsock error %d (could not load netmsg.dll to translate: error code %lu)", - errnum, GetLastError()); - return wserrbuf; + snprintf(buf, buflen, + "winsock error %d (could not load netmsg.dll to translate: error code %lu)", + errnum, GetLastError()); + return buf; } } - ZeroMemory(&wserrbuf, sizeof(wserrbuf)); + ZeroMemory(buf, buflen); if (FormatMessage(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_FROM_HMODULE, handleDLL, errnum, MAKELANGID(LANG_ENGLISH, SUBLANG_DEFAULT), - wserrbuf, - sizeof(wserrbuf) - 1, + buf, + buflen - 1, NULL) == 0) { /* Failed to get id */ - sprintf(wserrbuf, "unrecognized winsock error %d", errnum); + snprintf(buf, buflen, "unrecognized winsock error %d", errnum); } - return wserrbuf; + return buf; } #endif /* WIN32 */ |