Implement av_strerror().

Originally committed as revision 22684 to svn://svn.ffmpeg.org/ffmpeg/trunk

configure

@@ -1074,6 +1074,7 @@ HAVE_LIST="
     soundcard_h
     poll_h
     setrlimit
+    strerror_r
     struct_addrinfo
     struct_ipv6_mreq
     struct_sockaddr_in6
@@ -2531,6 +2532,7 @@ check_func  ${malloc_prefix}memalign            && enable memalign
 check_func  mkstemp
 check_func  ${malloc_prefix}posix_memalign      && enable posix_memalign
 check_func  setrlimit
+check_func  strerror_r
 check_func_headers io.h setmode
 check_func_headers lzo/lzo1x.h lzo1x_999_compress
 check_lib2 "windows.h psapi.h" GetProcessMemoryInfo -lpsapi

libavutil/Makefile

@@ -30,6 +30,7 @@ OBJS = adler32.o                                                        \
        base64.o                                                         \
        crc.o                                                            \
        des.o                                                            \
+       error.o                                                          \
        fifo.o                                                           \
        intfloat_readwrite.o                                             \
        lfg.o                                                            \

libavutil/avutil.h

@@ -40,7 +40,7 @@
 #define AV_VERSION(a, b, c) AV_VERSION_DOT(a, b, c)
 
 #define LIBAVUTIL_VERSION_MAJOR 50
-#define LIBAVUTIL_VERSION_MINOR 12
+#define LIBAVUTIL_VERSION_MINOR 13
 #define LIBAVUTIL_VERSION_MICRO  0
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \

libavutil/error.c

@@ -0,0 +1,46 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avutil.h"
+#include "avstring.h"
+
+int av_strerror(int errnum, char *errbuf, size_t errbuf_size)
+{
+    int ret = 0;
+    const char *errstr = NULL;
+
+    switch (errnum) {
+    case AVERROR_EOF:               errstr = "End of file"; break;
+    case AVERROR_INVALIDDATA:       errstr = "Invalid data found when processing input"; break;
+    case AVERROR_NOTSUPP:           errstr = "Operation not supported"; break;
+    case AVERROR_NUMEXPECTED:       errstr = "Number syntax expected in filename"; break;
+    case AVERROR_PATCHWELCOME:      errstr = "Not yet implemented in FFmpeg, patches welcome"; break;
+    }
+
+    if (errstr) {
+        av_strlcpy(errbuf, errstr, errbuf_size);
+    } else {
+#if HAVE_STRERROR_R
+        ret = strerror_r(AVUNERROR(errnum), errbuf, errbuf_size);
+#else
+        snprintf(errbuf, errbuf_size, "Error number %d occurred", errnum);
+#endif
+    }
+
+    return ret;
+}

libavutil/error.h

@@ -57,4 +57,14 @@
 #define AVERROR_NUMEXPECTED     (-MKTAG('N','U','E','X')) ///< Number syntax expected in filename
 #endif
 
+/**
+ * Puts a description of the AVERROR code errnum in errbuf.
+ * In case of failure the global variable errno is set to indicate the
+ * error.
+ *
+ * @param errbuf_size the size in bytes of errbuf
+ * @return 0 on success, a negative value otherwise
+ */
+int av_strerror(int errnum, char *errbuf, size_t errbuf_size);
+
 #endif /* AVUTIL_ERROR_H */