libavutil/avstring.h

   1 /*
   2  * Copyright (c) 2007 Mans Rullgard
   3  *
   4  * This file is part of FFmpeg.
   5  *
   6  * FFmpeg is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * FFmpeg is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with FFmpeg; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #ifndef AVUTIL_AVSTRING_H
  22 #define AVUTIL_AVSTRING_H
  23
  24 #include <stddef.h>
  25
  26 /**
  27  * Return non-zero if pfx is a prefix of str. If it is, *ptr is set to
  28  * the address of the first character in str after the prefix.
  29  *
  30  * @param str input string
  31  * @param pfx prefix to test
  32  * @param ptr updated if the prefix is matched inside str
  33  * @return non-zero if the prefix matches, zero otherwise
  34  */
  35 int av_strstart(const char *str, const char *pfx, const char **ptr);
  36
  37 /**
  38  * Return non-zero if pfx is a prefix of str independent of case. If
  39  * it is, *ptr is set to the address of the first character in str
  40  * after the prefix.
  41  *
  42  * @param str input string
  43  * @param pfx prefix to test
  44  * @param ptr updated if the prefix is matched inside str
  45  * @return non-zero if the prefix matches, zero otherwise
  46  */
  47 int av_stristart(const char *str, const char *pfx, const char **ptr);
  48
  49 /**
  50  * Copy the string src to dst, but no more than size - 1 bytes, and
  51  * null-terminate dst.
  52  *
  53  * This function is the same as BSD strlcpy().
  54  *
  55  * @param dst destination buffer
  56  * @param src source string
  57  * @param size size of destination buffer
  58  * @return the length of src
  59  *
  60  * WARNING: since the return value is the length of src, src absolutely
  61  * _must_ be a properly 0-terminated string, otherwise this will read beyond
  62  * the end of the buffer and possibly crash.
  63  */
  64 size_t av_strlcpy(char *dst, const char *src, size_t size);
  65
  66 /**
  67  * Append the string src to the string dst, but to a total length of
  68  * no more than size - 1 bytes, and null-terminate dst.
  69  *
  70  * This function is similar to BSD strlcat(), but differs when
  71  * size <= strlen(dst).
  72  *
  73  * @param dst destination buffer
  74  * @param src source string
  75  * @param size size of destination buffer
  76  * @return the total length of src and dst
  77  *
  78  * WARNING: since the return value use the length of src and dst, these absolutely
  79  * _must_ be a properly 0-terminated strings, otherwise this will read beyond
  80  * the end of the buffer and possibly crash.
  81  */
  82 size_t av_strlcat(char *dst, const char *src, size_t size);
  83
  84 /**
  85  * Append output to a string, according to a format. Never write out of
  86  * the destination buffer, and and always put a terminating 0 within
  87  * the buffer.
  88  * @param dst destination buffer (string to which the output is
  89  *  appended)
  90  * @param size total size of the destination buffer
  91  * @param fmt printf-compatible format string, specifying how the
  92  *  following parameters are used
  93  * @return the length of the string that would have been generated
  94  *  if enough space had been available
  95  */
  96 size_t av_strlcatf(char *dst, size_t size, const char *fmt, ...);
  97
  98 #endif /* AVUTIL_AVSTRING_H */