/*
  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
  * Copyright (c) 2007 Mans Rullgard
  *
  * 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 <stdarg.h>

 #include <stdint.h>

 #include <stdio.h>

 #include <string.h>

 #include "config.h"
 #include "common.h"

 #include "mem.h"

 #include "avassert.h"

 #include "avstring.h"

 #include "bprint.h"

 
 int av_strstart(const char *str, const char *pfx, const char **ptr)
 {

     while (*pfx && *pfx == *str) {
         pfx++;
         str++;
     }

     if (!*pfx && ptr)
         *ptr = str;
     return !*pfx;
 }
 
 int av_stristart(const char *str, const char *pfx, const char **ptr)
 {

     while (*pfx && av_toupper((unsigned)*pfx) == av_toupper((unsigned)*str)) {

         pfx++;
         str++;
     }

     if (!*pfx && ptr)
         *ptr = str;
     return !*pfx;
 }
 

 char *av_stristr(const char *s1, const char *s2)
 {
     if (!*s2)

         return (char*)(intptr_t)s1;

     do

         if (av_stristart(s1, s2, NULL))

             return (char*)(intptr_t)s1;

     while (*s1++);

 
     return NULL;
 }
 

 char *av_strnstr(const char *haystack, const char *needle, size_t hay_length)
 {
     size_t needle_len = strlen(needle);
     if (!needle_len)

         return (char*)haystack;

     while (hay_length >= needle_len) {
         hay_length--;
         if (!memcmp(haystack, needle, needle_len))

             return (char*)haystack;

         haystack++;
     }
     return NULL;
 }
 

 size_t av_strlcpy(char *dst, const char *src, size_t size)
 {
     size_t len = 0;
     while (++len < size && *src)
         *dst++ = *src++;
     if (len <= size)
         *dst = 0;
     return len + strlen(src) - 1;
 }
 
 size_t av_strlcat(char *dst, const char *src, size_t size)
 {
     size_t len = strlen(dst);
     if (size <= len + 1)
         return len + strlen(src);
     return len + av_strlcpy(dst + len, src, size - len);
 }

 
 size_t av_strlcatf(char *dst, size_t size, const char *fmt, ...)
 {

     size_t len = strlen(dst);

     va_list vl;
 
     va_start(vl, fmt);
     len += vsnprintf(dst + len, size > len ? size - len : 0, fmt, vl);
     va_end(vl);
 
     return len;
 }

 char *av_asprintf(const char *fmt, ...)
 {
     char *p = NULL;
     va_list va;
     int len;
 
     va_start(va, fmt);
     len = vsnprintf(NULL, 0, fmt, va);
     va_end(va);
     if (len < 0)
         goto end;
 
     p = av_malloc(len + 1);
     if (!p)
         goto end;
 
     va_start(va, fmt);
     len = vsnprintf(p, len + 1, fmt, va);
     va_end(va);
     if (len < 0)
         av_freep(&p);
 
 end:
     return p;
 }
 

 char *av_d2str(double d)
 {

     char *str = av_malloc(16);
     if (str)
         snprintf(str, 16, "%f", d);

     return str;
 }

 #define WHITESPACES " \n\t\r"

 
 char *av_get_token(const char **buf, const char *term)
 {

     char *out     = av_malloc(strlen(*buf) + 1);
     char *ret     = out, *end = out;

     const char *p = *buf;

     if (!out)
         return NULL;

     p += strspn(p, WHITESPACES);
 

     while (*p && !strspn(p, term)) {

         char c = *p++;

         if (c == '\\' && *p) {

             *out++ = *p++;

             end    = out;
         } else if (c == '\'') {
             while (*p && *p != '\'')

                 *out++ = *p++;

             if (*p) {

                 p++;

                 end = out;

             }

         } else {

             *out++ = c;
         }
     }
 

     do

         *out-- = 0;

     while (out >= end && strspn(out, WHITESPACES));

 
     *buf = p;
 
     return ret;
 }
 

 char *av_strtok(char *s, const char *delim, char **saveptr)
 {
     char *tok;
 
     if (!s && !(s = *saveptr))
         return NULL;
 
     /* skip leading delimiters */
     s += strspn(s, delim);
 
     /* s now points to the first non delimiter char, or to the end of the string */
     if (!*s) {
         *saveptr = NULL;
         return NULL;
     }
     tok = s++;
 
     /* skip non delimiters */
     s += strcspn(s, delim);
     if (*s) {
         *s = 0;
         *saveptr = s+1;
     } else {
         *saveptr = NULL;
     }
 
     return tok;
 }
 

 int av_strcasecmp(const char *a, const char *b)
 {
     uint8_t c1, c2;
     do {

         c1 = av_tolower(*a++);
         c2 = av_tolower(*b++);

     } while (c1 && c1 == c2);
     return c1 - c2;
 }
 
 int av_strncasecmp(const char *a, const char *b, size_t n)
 {
     const char *end = a + n;
     uint8_t c1, c2;
     do {

         c1 = av_tolower(*a++);
         c2 = av_tolower(*b++);

     } while (a < end && c1 && c1 == c2);
     return c1 - c2;
 }
 

 char *av_strireplace(const char *str, const char *from, const char *to)

 {

     char *ret = NULL;

     const char *pstr2, *pstr = str;

     size_t tolen = strlen(to), fromlen = strlen(from);
     AVBPrint pbuf;

     av_bprint_init(&pbuf, 1, AV_BPRINT_SIZE_UNLIMITED);

     while ((pstr2 = av_stristr(pstr, from))) {

         av_bprint_append_data(&pbuf, pstr, pstr2 - pstr);

         pstr = pstr2 + fromlen;

         av_bprint_append_data(&pbuf, to, tolen);

     }

     av_bprint_append_data(&pbuf, pstr, strlen(pstr));
     if (!av_bprint_is_complete(&pbuf)) {
         av_bprint_finalize(&pbuf, NULL);

     } else {

         av_bprint_finalize(&pbuf, &ret);

     }
 
     return ret;
 }
 

 const char *av_basename(const char *path)
 {
     char *p = strrchr(path, '/');
 
 #if HAVE_DOS_PATHS
     char *q = strrchr(path, '\\');
     char *d = strchr(path, ':');
 
     p = FFMAX3(p, q, d);
 #endif
 
     if (!p)
         return path;
 
     return p + 1;
 }
 
 const char *av_dirname(char *path)
 {
     char *p = strrchr(path, '/');
 
 #if HAVE_DOS_PATHS
     char *q = strrchr(path, '\\');
     char *d = strchr(path, ':');
 
     d = d ? d + 1 : d;
 
     p = FFMAX3(p, q, d);
 #endif
 
     if (!p)
         return ".";
 
     *p = '\0';
 
     return path;
 }
 

 char *av_append_path_component(const char *path, const char *component)
 {
     size_t p_len, c_len;
     char *fullpath;
 
     if (!path)
         return av_strdup(component);
     if (!component)
         return av_strdup(path);
 
     p_len = strlen(path);
     c_len = strlen(component);
     if (p_len > SIZE_MAX - c_len || p_len + c_len > SIZE_MAX - 2)
         return NULL;
     fullpath = av_malloc(p_len + c_len + 2);
     if (fullpath) {
         if (p_len) {
             av_strlcpy(fullpath, path, p_len + 1);
             if (c_len) {
                 if (fullpath[p_len - 1] != '/' && component[0] != '/')
                     fullpath[p_len++] = '/';
                 else if (fullpath[p_len - 1] == '/' && component[0] == '/')
                     p_len--;
             }
         }
         av_strlcpy(&fullpath[p_len], component, c_len + 1);
         fullpath[p_len + c_len] = 0;
     }
     return fullpath;
 }
 

 int av_escape(char **dst, const char *src, const char *special_chars,
               enum AVEscapeMode mode, int flags)
 {
     AVBPrint dstbuf;
 
     av_bprint_init(&dstbuf, 1, AV_BPRINT_SIZE_UNLIMITED);
     av_bprint_escape(&dstbuf, src, special_chars, mode, flags);
 
     if (!av_bprint_is_complete(&dstbuf)) {
         av_bprint_finalize(&dstbuf, NULL);
         return AVERROR(ENOMEM);
     } else {
         av_bprint_finalize(&dstbuf, dst);
         return dstbuf.len;
     }
 }
 

 int av_match_name(const char *name, const char *names)
 {
     const char *p;
     int len, namelen;
 
     if (!name || !names)
         return 0;
 
     namelen = strlen(name);

     while (*names) {
         int negate = '-' == *names;
         p = strchr(names, ',');
         if (!p)
             p = names + strlen(names);
         names += negate;

         len = FFMAX(p - names, namelen);

         if (!av_strncasecmp(name, names, len) || !strncmp("ALL", names, FFMAX(3, p - names)))
             return !negate;
         names = p + (*p == ',');

     }

     return 0;

 }
 

 int av_utf8_decode(int32_t *codep, const uint8_t **bufp, const uint8_t *buf_end,
                    unsigned int flags)
 {
     const uint8_t *p = *bufp;
     uint32_t top;
     uint64_t code;

     int ret = 0, tail_len;
     uint32_t overlong_encoding_mins[6] = {
         0x00000000, 0x00000080, 0x00000800, 0x00010000, 0x00200000, 0x04000000,
     };

 
     if (p >= buf_end)
         return 0;
 
     code = *p++;
 
     /* first sequence byte starts with 10, or is 1111-1110 or 1111-1111,
        which is not admitted */
     if ((code & 0xc0) == 0x80 || code >= 0xFE) {
         ret = AVERROR(EILSEQ);
         goto end;
     }
     top = (code & 128) >> 1;
 

     tail_len = 0;

     while (code & top) {
         int tmp;

         tail_len++;

         if (p >= buf_end) {

             (*bufp) ++;
             return AVERROR(EILSEQ); /* incomplete sequence */

         }
 
         /* we assume the byte to be in the form 10xx-xxxx */
         tmp = *p++ - 128;   /* strip leading 1 */
         if (tmp>>6) {

             (*bufp) ++;
             return AVERROR(EILSEQ);

         }
         code = (code<<6) + tmp;
         top <<= 5;
     }
     code &= (top << 1) - 1;
 

     /* check for overlong encodings */
     av_assert0(tail_len <= 5);
     if (code < overlong_encoding_mins[tail_len]) {
         ret = AVERROR(EILSEQ);
         goto end;
     }
 

     if (code >= 1U<<31) {

         ret = AVERROR(EILSEQ);  /* out-of-range value */
         goto end;
     }
 
     *codep = code;
 
     if (code > 0x10FFFF &&
         !(flags & AV_UTF8_FLAG_ACCEPT_INVALID_BIG_CODES))
         ret = AVERROR(EILSEQ);
     if (code < 0x20 && code != 0x9 && code != 0xA && code != 0xD &&
         flags & AV_UTF8_FLAG_EXCLUDE_XML_INVALID_CONTROL_CODES)
         ret = AVERROR(EILSEQ);
     if (code >= 0xD800 && code <= 0xDFFF &&
         !(flags & AV_UTF8_FLAG_ACCEPT_SURROGATES))
         ret = AVERROR(EILSEQ);

     if ((code == 0xFFFE || code == 0xFFFF) &&
         !(flags & AV_UTF8_FLAG_ACCEPT_NON_CHARACTERS))

         ret = AVERROR(EILSEQ);
 
 end:
     *bufp = p;
     return ret;
 }
 

 int av_match_list(const char *name, const char *list, char separator)
 {

     const char *p, *q;
 
     for (p = name; p && *p; ) {
         for (q = list; q && *q; ) {
             int k;

             for (k = 0; p[k] == q[k] || (p[k]*q[k] == 0 && p[k]+q[k] == separator); k++)
                 if (k && (!p[k] || p[k] == separator))

                     return 1;

             q = strchr(q, separator);

             q += !!q;
         }

         p = strchr(p, separator);

         p += !!p;

     }

     return 0;
 }