src/text/memstream.c

   1 /*****************************************************************************
   2  * memstream.c: heap-based output streams
   3  *****************************************************************************
   4  * Copyright (C) 2016 Rémi Denis-Courmont
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU Lesser General Public License as published by
   8  * the Free Software Foundation; either version 2.1 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program 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
  14  * GNU Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include "config.h"
  23 #endif
  24
  25 #include <vlc_common.h>
  26 #include <vlc_memstream.h>
  27
  28 #ifdef HAVE_OPEN_MEMSTREAM
  29 int vlc_memstream_open(struct vlc_memstream *ms)
  30 {
  31     ms->stream = open_memstream(&ms->ptr, &ms->length);
  32     return likely(ms->stream != NULL) ? 0 : EOF;
  33 }
  34
  35 int vlc_memstream_flush(struct vlc_memstream *ms)
  36 {
  37     if (unlikely(ms->stream == NULL))
  38         return EOF;
  39
  40     if (ferror(ms->stream))
  41         return EOF;
  42
  43     return fflush(ms->stream);
  44 }
  45
  46 int vlc_memstream_close(struct vlc_memstream *ms)
  47 {
  48     FILE *stream = ms->stream;
  49     int ret;
  50
  51     if (unlikely(stream == NULL))
  52         return EOF;
  53
  54     ms->stream = NULL;
  55     ret = ferror(stream);
  56
  57     if (fclose(stream))
  58         return EOF;
  59
  60     if (unlikely(ret))
  61     {
  62         free(ms->ptr);
  63         return EOF;
  64     }
  65     return 0;
  66 }
  67
  68 size_t vlc_memstream_write(struct vlc_memstream *ms, const void *ptr,
  69                            size_t len)
  70 {
  71     if (unlikely(ms->stream == NULL))
  72         return 0;
  73
  74     return fwrite(ptr, 1, len, ms->stream);
  75 }
  76
  77 int vlc_memstream_putc(struct vlc_memstream *ms, int c)
  78 {
  79     if (unlikely(ms->stream == NULL))
  80         return EOF;
  81
  82     return fputc(c, ms->stream);
  83 }
  84
  85 int (vlc_memstream_puts)(struct vlc_memstream *ms, const char *str)
  86 {
  87     if (unlikely(ms->stream == NULL))
  88         return EOF;
  89
  90     return fputs(str, ms->stream);
  91 }
  92
  93 int vlc_memstream_vprintf(struct vlc_memstream *ms, const char *fmt,
  94                           va_list args)
  95 {
  96     if (unlikely(ms->stream == NULL))
  97         return EOF;
  98
  99     return vfprintf(ms->stream, fmt, args);
 100 }
 101
 102 #else
 103 #include <stdlib.h>
 104
 105 int vlc_memstream_open(struct vlc_memstream *ms)
 106 {
 107     ms->error = 0;
 108     ms->ptr = calloc(1, 1);
 109     if (unlikely(ms->ptr == NULL))
 110         ms->error = EOF;
 111     ms->length = 0;
 112     return ms->error;
 113 }
 114
 115 int vlc_memstream_flush(struct vlc_memstream *ms)
 116 {
 117     return ms->error;
 118 }
 119
 120 int vlc_memstream_close(struct vlc_memstream *ms)
 121 {
 122     if (ms->error)
 123         free(ms->ptr);
 124     return ms->error;
 125 }
 126
 127 size_t vlc_memstream_write(struct vlc_memstream *ms, const void *ptr,
 128                            size_t len)
 129 {
 130     char *base = realloc(ms->ptr, ms->length + len + 1u);
 131     if (unlikely(base == NULL))
 132         goto error;
 133
 134     memcpy(base + ms->length, ptr, len);
 135     ms->ptr = base;
 136     ms->length += len;
 137     base[ms->length] = '\0';
 138     return len;
 139
 140 error:
 141     ms->error = EOF;
 142     return 0;
 143 }
 144
 145 int vlc_memstream_putc(struct vlc_memstream *ms, int c)
 146 {
 147     return (vlc_memstream_write(ms, &(unsigned char){ c }, 1u) == 1) ? c : EOF;
 148 }
 149
 150 int (vlc_memstream_puts)(struct vlc_memstream *ms, const char *str)
 151 {
 152     size_t len = strlen(str);
 153     return (vlc_memstream_write(ms, str, len) == len) ? 0 : EOF;
 154 }
 155
 156 int vlc_memstream_vprintf(struct vlc_memstream *ms, const char *fmt,
 157                           va_list args)
 158 {
 159     va_list ap;
 160     char *ptr;
 161     int len;
 162
 163     va_copy(ap, args);
 164     len = vsnprintf(NULL, 0, fmt, ap);
 165     va_end(ap);
 166
 167     if (len < 0)
 168         goto error;
 169
 170     ptr = realloc(ms->ptr, ms->length + len + 1);
 171     if (ptr == NULL)
 172         goto error;
 173
 174     vsnprintf(ptr + ms->length, len + 1, fmt, args);
 175     ms->ptr = ptr;
 176     ms->length += len;
 177     return len;
 178
 179 error:
 180     ms->error = EOF;
 181     return EOF;
 182 }
 183 #endif
 184
 185 int vlc_memstream_printf(struct vlc_memstream *ms, const char *fmt, ...)
 186 {
 187     va_list ap;
 188     int ret;
 189
 190     va_start(ap, fmt);
 191     ret = vlc_memstream_vprintf(ms, fmt, ap);
 192     va_end(ap);
 193     return ret;
 194 }