strbuf.c

   1 #include "cache.h"
   2 #include "refs.h"
   3
   4 int prefixcmp(const char *str, const char *prefix)
   5 {
   6         for (; ; str++, prefix++)
   7                 if (!*prefix)
   8                         return 0;
   9                 else if (*str != *prefix)
  10                         return (unsigned char)*prefix - (unsigned char)*str;
  11 }
  12
  13 int suffixcmp(const char *str, const char *suffix)
  14 {
  15         int len = strlen(str), suflen = strlen(suffix);
  16         if (len < suflen)
  17                 return -1;
  18         else
  19                 return strcmp(str + len - suflen, suffix);
  20 }
  21
  22 /*
  23  * Used as the default ->buf value, so that people can always assume
  24  * buf is non NULL and ->buf is NUL terminated even for a freshly
  25  * initialized strbuf.
  26  */
  27 char strbuf_slopbuf[1];
  28
  29 void strbuf_init(struct strbuf *sb, size_t hint)
  30 {
  31         sb->alloc = sb->len = 0;
  32         sb->buf = strbuf_slopbuf;
  33         if (hint)
  34                 strbuf_grow(sb, hint);
  35 }
  36
  37 void strbuf_release(struct strbuf *sb)
  38 {
  39         if (sb->alloc) {
  40                 free(sb->buf);
  41                 strbuf_init(sb, 0);
  42         }
  43 }
  44
  45 char *strbuf_detach(struct strbuf *sb, size_t *sz)
  46 {
  47         char *res = sb->alloc ? sb->buf : NULL;
  48         if (sz)
  49                 *sz = sb->len;
  50         strbuf_init(sb, 0);
  51         return res;
  52 }
  53
  54 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
  55 {
  56         strbuf_release(sb);
  57         sb->buf   = buf;
  58         sb->len   = len;
  59         sb->alloc = alloc;
  60         strbuf_grow(sb, 0);
  61         sb->buf[sb->len] = '\0';
  62 }
  63
  64 void strbuf_grow(struct strbuf *sb, size_t extra)
  65 {
  66         if (unsigned_add_overflows(extra, 1) ||
  67             unsigned_add_overflows(sb->len, extra + 1))
  68                 die("you want to use way too much memory");
  69         if (!sb->alloc)
  70                 sb->buf = NULL;
  71         ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
  72 }
  73
  74 void strbuf_trim(struct strbuf *sb)
  75 {
  76         char *b = sb->buf;
  77         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
  78                 sb->len--;
  79         while (sb->len > 0 && isspace(*b)) {
  80                 b++;
  81                 sb->len--;
  82         }
  83         memmove(sb->buf, b, sb->len);
  84         sb->buf[sb->len] = '\0';
  85 }
  86 void strbuf_rtrim(struct strbuf *sb)
  87 {
  88         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
  89                 sb->len--;
  90         sb->buf[sb->len] = '\0';
  91 }
  92
  93 void strbuf_ltrim(struct strbuf *sb)
  94 {
  95         char *b = sb->buf;
  96         while (sb->len > 0 && isspace(*b)) {
  97                 b++;
  98                 sb->len--;
  99         }
 100         memmove(sb->buf, b, sb->len);
 101         sb->buf[sb->len] = '\0';
 102 }
 103
 104 struct strbuf **strbuf_split(const struct strbuf *sb, int delim)
 105 {
 106         int alloc = 2, pos = 0;
 107         char *n, *p;
 108         struct strbuf **ret;
 109         struct strbuf *t;
 110
 111         ret = xcalloc(alloc, sizeof(struct strbuf *));
 112         p = n = sb->buf;
 113         while (n < sb->buf + sb->len) {
 114                 int len;
 115                 n = memchr(n, delim, sb->len - (n - sb->buf));
 116                 if (pos + 1 >= alloc) {
 117                         alloc = alloc * 2;
 118                         ret = xrealloc(ret, sizeof(struct strbuf *) * alloc);
 119                 }
 120                 if (!n)
 121                         n = sb->buf + sb->len - 1;
 122                 len = n - p + 1;
 123                 t = xmalloc(sizeof(struct strbuf));
 124                 strbuf_init(t, len);
 125                 strbuf_add(t, p, len);
 126                 ret[pos] = t;
 127                 ret[++pos] = NULL;
 128                 p = ++n;
 129         }
 130         return ret;
 131 }
 132
 133 void strbuf_list_free(struct strbuf **sbs)
 134 {
 135         struct strbuf **s = sbs;
 136
 137         while (*s) {
 138                 strbuf_release(*s);
 139                 free(*s++);
 140         }
 141         free(sbs);
 142 }
 143
 144 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 145 {
 146         int len = a->len < b->len ? a->len: b->len;
 147         int cmp = memcmp(a->buf, b->buf, len);
 148         if (cmp)
 149                 return cmp;
 150         return a->len < b->len ? -1: a->len != b->len;
 151 }
 152
 153 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 154                                    const void *data, size_t dlen)
 155 {
 156         if (unsigned_add_overflows(pos, len))
 157                 die("you want to use way too much memory");
 158         if (pos > sb->len)
 159                 die("`pos' is too far after the end of the buffer");
 160         if (pos + len > sb->len)
 161                 die("`pos + len' is too far after the end of the buffer");
 162
 163         if (dlen >= len)
 164                 strbuf_grow(sb, dlen - len);
 165         memmove(sb->buf + pos + dlen,
 166                         sb->buf + pos + len,
 167                         sb->len - pos - len);
 168         memcpy(sb->buf + pos, data, dlen);
 169         strbuf_setlen(sb, sb->len + dlen - len);
 170 }
 171
 172 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 173 {
 174         strbuf_splice(sb, pos, 0, data, len);
 175 }
 176
 177 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 178 {
 179         strbuf_splice(sb, pos, len, NULL, 0);
 180 }
 181
 182 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 183 {
 184         strbuf_grow(sb, len);
 185         memcpy(sb->buf + sb->len, data, len);
 186         strbuf_setlen(sb, sb->len + len);
 187 }
 188
 189 void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 190 {
 191         strbuf_grow(sb, len);
 192         memcpy(sb->buf + sb->len, sb->buf + pos, len);
 193         strbuf_setlen(sb, sb->len + len);
 194 }
 195
 196 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 197 {
 198         int len;
 199         va_list ap;
 200
 201         if (!strbuf_avail(sb))
 202                 strbuf_grow(sb, 64);
 203         va_start(ap, fmt);
 204         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 205         va_end(ap);
 206         if (len < 0)
 207                 die("your vsnprintf is broken");
 208         if (len > strbuf_avail(sb)) {
 209                 strbuf_grow(sb, len);
 210                 va_start(ap, fmt);
 211                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 212                 va_end(ap);
 213                 if (len > strbuf_avail(sb)) {
 214                         die("this should not happen, your snprintf is broken");
 215                 }
 216         }
 217         strbuf_setlen(sb, sb->len + len);
 218 }
 219
 220 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 221                    void *context)
 222 {
 223         for (;;) {
 224                 const char *percent;
 225                 size_t consumed;
 226
 227                 percent = strchrnul(format, '%');
 228                 strbuf_add(sb, format, percent - format);
 229                 if (!*percent)
 230                         break;
 231                 format = percent + 1;
 232
 233                 if (*format == '%') {
 234                         strbuf_addch(sb, '%');
 235                         format++;
 236                         continue;
 237                 }
 238
 239                 consumed = fn(sb, format, context);
 240                 if (consumed)
 241                         format += consumed;
 242                 else
 243                         strbuf_addch(sb, '%');
 244         }
 245 }
 246
 247 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 248                 void *context)
 249 {
 250         struct strbuf_expand_dict_entry *e = context;
 251         size_t len;
 252
 253         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 254                 if (!strncmp(placeholder, e->placeholder, len)) {
 255                         if (e->value)
 256                                 strbuf_addstr(sb, e->value);
 257                         return len;
 258                 }
 259         }
 260         return 0;
 261 }
 262
 263 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 264 {
 265         int i, len = src->len;
 266
 267         for (i = 0; i < len; i++) {
 268                 if (src->buf[i] == '%')
 269                         strbuf_addch(dst, '%');
 270                 strbuf_addch(dst, src->buf[i]);
 271         }
 272 }
 273
 274 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 275 {
 276         size_t res;
 277         size_t oldalloc = sb->alloc;
 278
 279         strbuf_grow(sb, size);
 280         res = fread(sb->buf + sb->len, 1, size, f);
 281         if (res > 0)
 282                 strbuf_setlen(sb, sb->len + res);
 283         else if (oldalloc == 0)
 284                 strbuf_release(sb);
 285         return res;
 286 }
 287
 288 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 289 {
 290         size_t oldlen = sb->len;
 291         size_t oldalloc = sb->alloc;
 292
 293         strbuf_grow(sb, hint ? hint : 8192);
 294         for (;;) {
 295                 ssize_t cnt;
 296
 297                 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 298                 if (cnt < 0) {
 299                         if (oldalloc == 0)
 300                                 strbuf_release(sb);
 301                         else
 302                                 strbuf_setlen(sb, oldlen);
 303                         return -1;
 304                 }
 305                 if (!cnt)
 306                         break;
 307                 sb->len += cnt;
 308                 strbuf_grow(sb, 8192);
 309         }
 310
 311         sb->buf[sb->len] = '\0';
 312         return sb->len - oldlen;
 313 }
 314
 315 #define STRBUF_MAXLINK (2*PATH_MAX)
 316
 317 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 318 {
 319         size_t oldalloc = sb->alloc;
 320
 321         if (hint < 32)
 322                 hint = 32;
 323
 324         while (hint < STRBUF_MAXLINK) {
 325                 int len;
 326
 327                 strbuf_grow(sb, hint);
 328                 len = readlink(path, sb->buf, hint);
 329                 if (len < 0) {
 330                         if (errno != ERANGE)
 331                                 break;
 332                 } else if (len < hint) {
 333                         strbuf_setlen(sb, len);
 334                         return 0;
 335                 }
 336
 337                 /* .. the buffer was too small - try again */
 338                 hint *= 2;
 339         }
 340         if (oldalloc == 0)
 341                 strbuf_release(sb);
 342         return -1;
 343 }
 344
 345 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 346 {
 347         int ch;
 348
 349         strbuf_grow(sb, 0);
 350         if (feof(fp))
 351                 return EOF;
 352
 353         strbuf_reset(sb);
 354         while ((ch = fgetc(fp)) != EOF) {
 355                 strbuf_grow(sb, 1);
 356                 sb->buf[sb->len++] = ch;
 357                 if (ch == term)
 358                         break;
 359         }
 360         if (ch == EOF && sb->len == 0)
 361                 return EOF;
 362
 363         sb->buf[sb->len] = '\0';
 364         return 0;
 365 }
 366
 367 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 368 {
 369         if (strbuf_getwholeline(sb, fp, term))
 370                 return EOF;
 371         if (sb->buf[sb->len-1] == term)
 372                 strbuf_setlen(sb, sb->len-1);
 373         return 0;
 374 }
 375
 376 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 377 {
 378         int fd, len;
 379
 380         fd = open(path, O_RDONLY);
 381         if (fd < 0)
 382                 return -1;
 383         len = strbuf_read(sb, fd, hint);
 384         close(fd);
 385         if (len < 0)
 386                 return -1;
 387
 388         return len;
 389 }