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         int new_buf = !sb->alloc;
  67         if (unsigned_add_overflows(extra, 1) ||
  68             unsigned_add_overflows(sb->len, extra + 1))
  69                 die("you want to use way too much memory");
  70         if (new_buf)
  71                 sb->buf = NULL;
  72         ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
  73         if (new_buf)
  74                 sb->buf[0] = '\0';
  75 }
  76
  77 void strbuf_trim(struct strbuf *sb)
  78 {
  79         char *b = sb->buf;
  80         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
  81                 sb->len--;
  82         while (sb->len > 0 && isspace(*b)) {
  83                 b++;
  84                 sb->len--;
  85         }
  86         memmove(sb->buf, b, sb->len);
  87         sb->buf[sb->len] = '\0';
  88 }
  89 void strbuf_rtrim(struct strbuf *sb)
  90 {
  91         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
  92                 sb->len--;
  93         sb->buf[sb->len] = '\0';
  94 }
  95
  96 void strbuf_ltrim(struct strbuf *sb)
  97 {
  98         char *b = sb->buf;
  99         while (sb->len > 0 && isspace(*b)) {
 100                 b++;
 101                 sb->len--;
 102         }
 103         memmove(sb->buf, b, sb->len);
 104         sb->buf[sb->len] = '\0';
 105 }
 106
 107 struct strbuf **strbuf_split(const struct strbuf *sb, int delim)
 108 {
 109         int alloc = 2, pos = 0;
 110         char *n, *p;
 111         struct strbuf **ret;
 112         struct strbuf *t;
 113
 114         ret = xcalloc(alloc, sizeof(struct strbuf *));
 115         p = n = sb->buf;
 116         while (n < sb->buf + sb->len) {
 117                 int len;
 118                 n = memchr(n, delim, sb->len - (n - sb->buf));
 119                 if (pos + 1 >= alloc) {
 120                         alloc = alloc * 2;
 121                         ret = xrealloc(ret, sizeof(struct strbuf *) * alloc);
 122                 }
 123                 if (!n)
 124                         n = sb->buf + sb->len - 1;
 125                 len = n - p + 1;
 126                 t = xmalloc(sizeof(struct strbuf));
 127                 strbuf_init(t, len);
 128                 strbuf_add(t, p, len);
 129                 ret[pos] = t;
 130                 ret[++pos] = NULL;
 131                 p = ++n;
 132         }
 133         return ret;
 134 }
 135
 136 void strbuf_list_free(struct strbuf **sbs)
 137 {
 138         struct strbuf **s = sbs;
 139
 140         while (*s) {
 141                 strbuf_release(*s);
 142                 free(*s++);
 143         }
 144         free(sbs);
 145 }
 146
 147 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 148 {
 149         int len = a->len < b->len ? a->len: b->len;
 150         int cmp = memcmp(a->buf, b->buf, len);
 151         if (cmp)
 152                 return cmp;
 153         return a->len < b->len ? -1: a->len != b->len;
 154 }
 155
 156 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 157                                    const void *data, size_t dlen)
 158 {
 159         if (unsigned_add_overflows(pos, len))
 160                 die("you want to use way too much memory");
 161         if (pos > sb->len)
 162                 die("`pos' is too far after the end of the buffer");
 163         if (pos + len > sb->len)
 164                 die("`pos + len' is too far after the end of the buffer");
 165
 166         if (dlen >= len)
 167                 strbuf_grow(sb, dlen - len);
 168         memmove(sb->buf + pos + dlen,
 169                         sb->buf + pos + len,
 170                         sb->len - pos - len);
 171         memcpy(sb->buf + pos, data, dlen);
 172         strbuf_setlen(sb, sb->len + dlen - len);
 173 }
 174
 175 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 176 {
 177         strbuf_splice(sb, pos, 0, data, len);
 178 }
 179
 180 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 181 {
 182         strbuf_splice(sb, pos, len, NULL, 0);
 183 }
 184
 185 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 186 {
 187         strbuf_grow(sb, len);
 188         memcpy(sb->buf + sb->len, data, len);
 189         strbuf_setlen(sb, sb->len + len);
 190 }
 191
 192 void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 193 {
 194         strbuf_grow(sb, len);
 195         memcpy(sb->buf + sb->len, sb->buf + pos, len);
 196         strbuf_setlen(sb, sb->len + len);
 197 }
 198
 199 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 200 {
 201         va_list ap;
 202         va_start(ap, fmt);
 203         strbuf_vaddf(sb, fmt, ap);
 204         va_end(ap);
 205 }
 206
 207 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 208 {
 209         int len;
 210         va_list cp;
 211
 212         if (!strbuf_avail(sb))
 213                 strbuf_grow(sb, 64);
 214         va_copy(cp, ap);
 215         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 216         va_end(cp);
 217         if (len < 0)
 218                 die("BUG: your vsnprintf is broken (returned %d)", len);
 219         if (len > strbuf_avail(sb)) {
 220                 strbuf_grow(sb, len);
 221                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 222                 if (len > strbuf_avail(sb))
 223                         die("BUG: your vsnprintf is broken (insatiable)");
 224         }
 225         strbuf_setlen(sb, sb->len + len);
 226 }
 227
 228 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 229                    void *context)
 230 {
 231         for (;;) {
 232                 const char *percent;
 233                 size_t consumed;
 234
 235                 percent = strchrnul(format, '%');
 236                 strbuf_add(sb, format, percent - format);
 237                 if (!*percent)
 238                         break;
 239                 format = percent + 1;
 240
 241                 if (*format == '%') {
 242                         strbuf_addch(sb, '%');
 243                         format++;
 244                         continue;
 245                 }
 246
 247                 consumed = fn(sb, format, context);
 248                 if (consumed)
 249                         format += consumed;
 250                 else
 251                         strbuf_addch(sb, '%');
 252         }
 253 }
 254
 255 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 256                 void *context)
 257 {
 258         struct strbuf_expand_dict_entry *e = context;
 259         size_t len;
 260
 261         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 262                 if (!strncmp(placeholder, e->placeholder, len)) {
 263                         if (e->value)
 264                                 strbuf_addstr(sb, e->value);
 265                         return len;
 266                 }
 267         }
 268         return 0;
 269 }
 270
 271 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 272 {
 273         int i, len = src->len;
 274
 275         for (i = 0; i < len; i++) {
 276                 if (src->buf[i] == '%')
 277                         strbuf_addch(dst, '%');
 278                 strbuf_addch(dst, src->buf[i]);
 279         }
 280 }
 281
 282 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 283 {
 284         size_t res;
 285         size_t oldalloc = sb->alloc;
 286
 287         strbuf_grow(sb, size);
 288         res = fread(sb->buf + sb->len, 1, size, f);
 289         if (res > 0)
 290                 strbuf_setlen(sb, sb->len + res);
 291         else if (oldalloc == 0)
 292                 strbuf_release(sb);
 293         return res;
 294 }
 295
 296 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 297 {
 298         size_t oldlen = sb->len;
 299         size_t oldalloc = sb->alloc;
 300
 301         strbuf_grow(sb, hint ? hint : 8192);
 302         for (;;) {
 303                 ssize_t cnt;
 304
 305                 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 306                 if (cnt < 0) {
 307                         if (oldalloc == 0)
 308                                 strbuf_release(sb);
 309                         else
 310                                 strbuf_setlen(sb, oldlen);
 311                         return -1;
 312                 }
 313                 if (!cnt)
 314                         break;
 315                 sb->len += cnt;
 316                 strbuf_grow(sb, 8192);
 317         }
 318
 319         sb->buf[sb->len] = '\0';
 320         return sb->len - oldlen;
 321 }
 322
 323 #define STRBUF_MAXLINK (2*PATH_MAX)
 324
 325 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 326 {
 327         size_t oldalloc = sb->alloc;
 328
 329         if (hint < 32)
 330                 hint = 32;
 331
 332         while (hint < STRBUF_MAXLINK) {
 333                 int len;
 334
 335                 strbuf_grow(sb, hint);
 336                 len = readlink(path, sb->buf, hint);
 337                 if (len < 0) {
 338                         if (errno != ERANGE)
 339                                 break;
 340                 } else if (len < hint) {
 341                         strbuf_setlen(sb, len);
 342                         return 0;
 343                 }
 344
 345                 /* .. the buffer was too small - try again */
 346                 hint *= 2;
 347         }
 348         if (oldalloc == 0)
 349                 strbuf_release(sb);
 350         return -1;
 351 }
 352
 353 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 354 {
 355         int ch;
 356
 357         strbuf_grow(sb, 0);
 358         if (feof(fp))
 359                 return EOF;
 360
 361         strbuf_reset(sb);
 362         while ((ch = fgetc(fp)) != EOF) {
 363                 strbuf_grow(sb, 1);
 364                 sb->buf[sb->len++] = ch;
 365                 if (ch == term)
 366                         break;
 367         }
 368         if (ch == EOF && sb->len == 0)
 369                 return EOF;
 370
 371         sb->buf[sb->len] = '\0';
 372         return 0;
 373 }
 374
 375 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 376 {
 377         if (strbuf_getwholeline(sb, fp, term))
 378                 return EOF;
 379         if (sb->buf[sb->len-1] == term)
 380                 strbuf_setlen(sb, sb->len-1);
 381         return 0;
 382 }
 383
 384 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 385 {
 386         int fd, len;
 387
 388         fd = open(path, O_RDONLY);
 389         if (fd < 0)
 390                 return -1;
 391         len = strbuf_read(sb, fd, hint);
 392         close(fd);
 393         if (len < 0)
 394                 return -1;
 395
 396         return len;
 397 }