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                 sb->buf[0] = '\0';
  36         }
  37 }
  38
  39 void strbuf_release(struct strbuf *sb)
  40 {
  41         if (sb->alloc) {
  42                 free(sb->buf);
  43                 strbuf_init(sb, 0);
  44         }
  45 }
  46
  47 char *strbuf_detach(struct strbuf *sb, size_t *sz)
  48 {
  49         char *res = sb->alloc ? sb->buf : NULL;
  50         if (sz)
  51                 *sz = sb->len;
  52         strbuf_init(sb, 0);
  53         return res;
  54 }
  55
  56 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
  57 {
  58         strbuf_release(sb);
  59         sb->buf   = buf;
  60         sb->len   = len;
  61         sb->alloc = alloc;
  62         strbuf_grow(sb, 0);
  63         sb->buf[sb->len] = '\0';
  64 }
  65
  66 void strbuf_grow(struct strbuf *sb, size_t extra)
  67 {
  68         if (unsigned_add_overflows(extra, 1) ||
  69             unsigned_add_overflows(sb->len, extra + 1))
  70                 die("you want to use way too much memory");
  71         if (!sb->alloc)
  72                 sb->buf = NULL;
  73         ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
  74 }
  75
  76 void strbuf_trim(struct strbuf *sb)
  77 {
  78         char *b = sb->buf;
  79         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
  80                 sb->len--;
  81         while (sb->len > 0 && isspace(*b)) {
  82                 b++;
  83                 sb->len--;
  84         }
  85         memmove(sb->buf, b, sb->len);
  86         sb->buf[sb->len] = '\0';
  87 }
  88 void strbuf_rtrim(struct strbuf *sb)
  89 {
  90         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
  91                 sb->len--;
  92         sb->buf[sb->len] = '\0';
  93 }
  94
  95 void strbuf_ltrim(struct strbuf *sb)
  96 {
  97         char *b = sb->buf;
  98         while (sb->len > 0 && isspace(*b)) {
  99                 b++;
 100                 sb->len--;
 101         }
 102         memmove(sb->buf, b, sb->len);
 103         sb->buf[sb->len] = '\0';
 104 }
 105
 106 struct strbuf **strbuf_split(const struct strbuf *sb, int delim)
 107 {
 108         int alloc = 2, pos = 0;
 109         char *n, *p;
 110         struct strbuf **ret;
 111         struct strbuf *t;
 112
 113         ret = xcalloc(alloc, sizeof(struct strbuf *));
 114         p = n = sb->buf;
 115         while (n < sb->buf + sb->len) {
 116                 int len;
 117                 n = memchr(n, delim, sb->len - (n - sb->buf));
 118                 if (pos + 1 >= alloc) {
 119                         alloc = alloc * 2;
 120                         ret = xrealloc(ret, sizeof(struct strbuf *) * alloc);
 121                 }
 122                 if (!n)
 123                         n = sb->buf + sb->len - 1;
 124                 len = n - p + 1;
 125                 t = xmalloc(sizeof(struct strbuf));
 126                 strbuf_init(t, len);
 127                 strbuf_add(t, p, len);
 128                 ret[pos] = t;
 129                 ret[++pos] = NULL;
 130                 p = ++n;
 131         }
 132         return ret;
 133 }
 134
 135 void strbuf_list_free(struct strbuf **sbs)
 136 {
 137         struct strbuf **s = sbs;
 138
 139         while (*s) {
 140                 strbuf_release(*s);
 141                 free(*s++);
 142         }
 143         free(sbs);
 144 }
 145
 146 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 147 {
 148         int len = a->len < b->len ? a->len: b->len;
 149         int cmp = memcmp(a->buf, b->buf, len);
 150         if (cmp)
 151                 return cmp;
 152         return a->len < b->len ? -1: a->len != b->len;
 153 }
 154
 155 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 156                                    const void *data, size_t dlen)
 157 {
 158         if (unsigned_add_overflows(pos, len))
 159                 die("you want to use way too much memory");
 160         if (pos > sb->len)
 161                 die("`pos' is too far after the end of the buffer");
 162         if (pos + len > sb->len)
 163                 die("`pos + len' is too far after the end of the buffer");
 164
 165         if (dlen >= len)
 166                 strbuf_grow(sb, dlen - len);
 167         memmove(sb->buf + pos + dlen,
 168                         sb->buf + pos + len,
 169                         sb->len - pos - len);
 170         memcpy(sb->buf + pos, data, dlen);
 171         strbuf_setlen(sb, sb->len + dlen - len);
 172 }
 173
 174 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 175 {
 176         strbuf_splice(sb, pos, 0, data, len);
 177 }
 178
 179 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 180 {
 181         strbuf_splice(sb, pos, len, NULL, 0);
 182 }
 183
 184 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 185 {
 186         strbuf_grow(sb, len);
 187         memcpy(sb->buf + sb->len, data, len);
 188         strbuf_setlen(sb, sb->len + len);
 189 }
 190
 191 void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 192 {
 193         strbuf_grow(sb, len);
 194         memcpy(sb->buf + sb->len, sb->buf + pos, len);
 195         strbuf_setlen(sb, sb->len + len);
 196 }
 197
 198 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 199 {
 200         va_list ap;
 201         va_start(ap, fmt);
 202         strbuf_vaddf(sb, fmt, ap);
 203         va_end(ap);
 204 }
 205
 206 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 207 {
 208         int len;
 209         va_list cp;
 210
 211         if (!strbuf_avail(sb))
 212                 strbuf_grow(sb, 64);
 213         va_copy(cp, ap);
 214         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 215         va_end(cp);
 216         if (len < 0)
 217                 die("BUG: your vsnprintf is broken (returned %d)", len);
 218         if (len > strbuf_avail(sb)) {
 219                 strbuf_grow(sb, len);
 220                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 221                 if (len > strbuf_avail(sb))
 222                         die("BUG: your vsnprintf is broken (insatiable)");
 223         }
 224         strbuf_setlen(sb, sb->len + len);
 225 }
 226
 227 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 228                    void *context)
 229 {
 230         for (;;) {
 231                 const char *percent;
 232                 size_t consumed;
 233
 234                 percent = strchrnul(format, '%');
 235                 strbuf_add(sb, format, percent - format);
 236                 if (!*percent)
 237                         break;
 238                 format = percent + 1;
 239
 240                 if (*format == '%') {
 241                         strbuf_addch(sb, '%');
 242                         format++;
 243                         continue;
 244                 }
 245
 246                 consumed = fn(sb, format, context);
 247                 if (consumed)
 248                         format += consumed;
 249                 else
 250                         strbuf_addch(sb, '%');
 251         }
 252 }
 253
 254 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 255                 void *context)
 256 {
 257         struct strbuf_expand_dict_entry *e = context;
 258         size_t len;
 259
 260         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 261                 if (!strncmp(placeholder, e->placeholder, len)) {
 262                         if (e->value)
 263                                 strbuf_addstr(sb, e->value);
 264                         return len;
 265                 }
 266         }
 267         return 0;
 268 }
 269
 270 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 271 {
 272         int i, len = src->len;
 273
 274         for (i = 0; i < len; i++) {
 275                 if (src->buf[i] == '%')
 276                         strbuf_addch(dst, '%');
 277                 strbuf_addch(dst, src->buf[i]);
 278         }
 279 }
 280
 281 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 282 {
 283         size_t res;
 284         size_t oldalloc = sb->alloc;
 285
 286         strbuf_grow(sb, size);
 287         res = fread(sb->buf + sb->len, 1, size, f);
 288         if (res > 0)
 289                 strbuf_setlen(sb, sb->len + res);
 290         else if (oldalloc == 0)
 291                 strbuf_release(sb);
 292         return res;
 293 }
 294
 295 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 296 {
 297         size_t oldlen = sb->len;
 298         size_t oldalloc = sb->alloc;
 299
 300         strbuf_grow(sb, hint ? hint : 8192);
 301         for (;;) {
 302                 ssize_t cnt;
 303
 304                 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 305                 if (cnt < 0) {
 306                         if (oldalloc == 0)
 307                                 strbuf_release(sb);
 308                         else
 309                                 strbuf_setlen(sb, oldlen);
 310                         return -1;
 311                 }
 312                 if (!cnt)
 313                         break;
 314                 sb->len += cnt;
 315                 strbuf_grow(sb, 8192);
 316         }
 317
 318         sb->buf[sb->len] = '\0';
 319         return sb->len - oldlen;
 320 }
 321
 322 #define STRBUF_MAXLINK (2*PATH_MAX)
 323
 324 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 325 {
 326         size_t oldalloc = sb->alloc;
 327
 328         if (hint < 32)
 329                 hint = 32;
 330
 331         while (hint < STRBUF_MAXLINK) {
 332                 int len;
 333
 334                 strbuf_grow(sb, hint);
 335                 len = readlink(path, sb->buf, hint);
 336                 if (len < 0) {
 337                         if (errno != ERANGE)
 338                                 break;
 339                 } else if (len < hint) {
 340                         strbuf_setlen(sb, len);
 341                         return 0;
 342                 }
 343
 344                 /* .. the buffer was too small - try again */
 345                 hint *= 2;
 346         }
 347         if (oldalloc == 0)
 348                 strbuf_release(sb);
 349         return -1;
 350 }
 351
 352 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 353 {
 354         int ch;
 355
 356         strbuf_grow(sb, 0);
 357         if (feof(fp))
 358                 return EOF;
 359
 360         strbuf_reset(sb);
 361         while ((ch = fgetc(fp)) != EOF) {
 362                 strbuf_grow(sb, 1);
 363                 sb->buf[sb->len++] = ch;
 364                 if (ch == term)
 365                         break;
 366         }
 367         if (ch == EOF && sb->len == 0)
 368                 return EOF;
 369
 370         sb->buf[sb->len] = '\0';
 371         return 0;
 372 }
 373
 374 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 375 {
 376         if (strbuf_getwholeline(sb, fp, term))
 377                 return EOF;
 378         if (sb->buf[sb->len-1] == term)
 379                 strbuf_setlen(sb, sb->len-1);
 380         return 0;
 381 }
 382
 383 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 384 {
 385         int fd, len;
 386
 387         fd = open(path, O_RDONLY);
 388         if (fd < 0)
 389                 return -1;
 390         len = strbuf_read(sb, fd, hint);
 391         close(fd);
 392         if (len < 0)
 393                 return -1;
 394
 395         return len;
 396 }