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_buf(const char *str, size_t slen, int delim, int max)
 108 {
 109         int alloc = 2, pos = 0;
 110         const char *n, *p;
 111         struct strbuf **ret;
 112         struct strbuf *t;
 113
 114         ret = xcalloc(alloc, sizeof(struct strbuf *));
 115         p = n = str;
 116         while (n < str + slen) {
 117                 int len;
 118                 if (max <= 0 || pos + 1 < max)
 119                         n = memchr(n, delim, slen - (n - str));
 120                 else
 121                         n = NULL;
 122                 if (pos + 1 >= alloc) {
 123                         alloc = alloc * 2;
 124                         ret = xrealloc(ret, sizeof(struct strbuf *) * alloc);
 125                 }
 126                 if (!n)
 127                         n = str + slen - 1;
 128                 len = n - p + 1;
 129                 t = xmalloc(sizeof(struct strbuf));
 130                 strbuf_init(t, len);
 131                 strbuf_add(t, p, len);
 132                 ret[pos] = t;
 133                 ret[++pos] = NULL;
 134                 p = ++n;
 135         }
 136         return ret;
 137 }
 138
 139 void strbuf_list_free(struct strbuf **sbs)
 140 {
 141         struct strbuf **s = sbs;
 142
 143         while (*s) {
 144                 strbuf_release(*s);
 145                 free(*s++);
 146         }
 147         free(sbs);
 148 }
 149
 150 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 151 {
 152         int len = a->len < b->len ? a->len: b->len;
 153         int cmp = memcmp(a->buf, b->buf, len);
 154         if (cmp)
 155                 return cmp;
 156         return a->len < b->len ? -1: a->len != b->len;
 157 }
 158
 159 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 160                                    const void *data, size_t dlen)
 161 {
 162         if (unsigned_add_overflows(pos, len))
 163                 die("you want to use way too much memory");
 164         if (pos > sb->len)
 165                 die("`pos' is too far after the end of the buffer");
 166         if (pos + len > sb->len)
 167                 die("`pos + len' is too far after the end of the buffer");
 168
 169         if (dlen >= len)
 170                 strbuf_grow(sb, dlen - len);
 171         memmove(sb->buf + pos + dlen,
 172                         sb->buf + pos + len,
 173                         sb->len - pos - len);
 174         memcpy(sb->buf + pos, data, dlen);
 175         strbuf_setlen(sb, sb->len + dlen - len);
 176 }
 177
 178 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 179 {
 180         strbuf_splice(sb, pos, 0, data, len);
 181 }
 182
 183 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 184 {
 185         strbuf_splice(sb, pos, len, NULL, 0);
 186 }
 187
 188 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 189 {
 190         strbuf_grow(sb, len);
 191         memcpy(sb->buf + sb->len, data, len);
 192         strbuf_setlen(sb, sb->len + len);
 193 }
 194
 195 void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 196 {
 197         strbuf_grow(sb, len);
 198         memcpy(sb->buf + sb->len, sb->buf + pos, len);
 199         strbuf_setlen(sb, sb->len + len);
 200 }
 201
 202 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 203 {
 204         va_list ap;
 205         va_start(ap, fmt);
 206         strbuf_vaddf(sb, fmt, ap);
 207         va_end(ap);
 208 }
 209
 210 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 211 {
 212         int len;
 213         va_list cp;
 214
 215         if (!strbuf_avail(sb))
 216                 strbuf_grow(sb, 64);
 217         va_copy(cp, ap);
 218         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 219         va_end(cp);
 220         if (len < 0)
 221                 die("BUG: your vsnprintf is broken (returned %d)", len);
 222         if (len > strbuf_avail(sb)) {
 223                 strbuf_grow(sb, len);
 224                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 225                 if (len > strbuf_avail(sb))
 226                         die("BUG: your vsnprintf is broken (insatiable)");
 227         }
 228         strbuf_setlen(sb, sb->len + len);
 229 }
 230
 231 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 232                    void *context)
 233 {
 234         for (;;) {
 235                 const char *percent;
 236                 size_t consumed;
 237
 238                 percent = strchrnul(format, '%');
 239                 strbuf_add(sb, format, percent - format);
 240                 if (!*percent)
 241                         break;
 242                 format = percent + 1;
 243
 244                 if (*format == '%') {
 245                         strbuf_addch(sb, '%');
 246                         format++;
 247                         continue;
 248                 }
 249
 250                 consumed = fn(sb, format, context);
 251                 if (consumed)
 252                         format += consumed;
 253                 else
 254                         strbuf_addch(sb, '%');
 255         }
 256 }
 257
 258 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 259                 void *context)
 260 {
 261         struct strbuf_expand_dict_entry *e = context;
 262         size_t len;
 263
 264         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 265                 if (!strncmp(placeholder, e->placeholder, len)) {
 266                         if (e->value)
 267                                 strbuf_addstr(sb, e->value);
 268                         return len;
 269                 }
 270         }
 271         return 0;
 272 }
 273
 274 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 275 {
 276         int i, len = src->len;
 277
 278         for (i = 0; i < len; i++) {
 279                 if (src->buf[i] == '%')
 280                         strbuf_addch(dst, '%');
 281                 strbuf_addch(dst, src->buf[i]);
 282         }
 283 }
 284
 285 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 286 {
 287         size_t res;
 288         size_t oldalloc = sb->alloc;
 289
 290         strbuf_grow(sb, size);
 291         res = fread(sb->buf + sb->len, 1, size, f);
 292         if (res > 0)
 293                 strbuf_setlen(sb, sb->len + res);
 294         else if (oldalloc == 0)
 295                 strbuf_release(sb);
 296         return res;
 297 }
 298
 299 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 300 {
 301         size_t oldlen = sb->len;
 302         size_t oldalloc = sb->alloc;
 303
 304         strbuf_grow(sb, hint ? hint : 8192);
 305         for (;;) {
 306                 ssize_t cnt;
 307
 308                 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 309                 if (cnt < 0) {
 310                         if (oldalloc == 0)
 311                                 strbuf_release(sb);
 312                         else
 313                                 strbuf_setlen(sb, oldlen);
 314                         return -1;
 315                 }
 316                 if (!cnt)
 317                         break;
 318                 sb->len += cnt;
 319                 strbuf_grow(sb, 8192);
 320         }
 321
 322         sb->buf[sb->len] = '\0';
 323         return sb->len - oldlen;
 324 }
 325
 326 #define STRBUF_MAXLINK (2*PATH_MAX)
 327
 328 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 329 {
 330         size_t oldalloc = sb->alloc;
 331
 332         if (hint < 32)
 333                 hint = 32;
 334
 335         while (hint < STRBUF_MAXLINK) {
 336                 int len;
 337
 338                 strbuf_grow(sb, hint);
 339                 len = readlink(path, sb->buf, hint);
 340                 if (len < 0) {
 341                         if (errno != ERANGE)
 342                                 break;
 343                 } else if (len < hint) {
 344                         strbuf_setlen(sb, len);
 345                         return 0;
 346                 }
 347
 348                 /* .. the buffer was too small - try again */
 349                 hint *= 2;
 350         }
 351         if (oldalloc == 0)
 352                 strbuf_release(sb);
 353         return -1;
 354 }
 355
 356 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 357 {
 358         int ch;
 359
 360         if (feof(fp))
 361                 return EOF;
 362
 363         strbuf_reset(sb);
 364         while ((ch = fgetc(fp)) != EOF) {
 365                 strbuf_grow(sb, 1);
 366                 sb->buf[sb->len++] = ch;
 367                 if (ch == term)
 368                         break;
 369         }
 370         if (ch == EOF && sb->len == 0)
 371                 return EOF;
 372
 373         sb->buf[sb->len] = '\0';
 374         return 0;
 375 }
 376
 377 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 378 {
 379         if (strbuf_getwholeline(sb, fp, term))
 380                 return EOF;
 381         if (sb->buf[sb->len-1] == term)
 382                 strbuf_setlen(sb, sb->len-1);
 383         return 0;
 384 }
 385
 386 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 387 {
 388         int fd, len;
 389
 390         fd = open(path, O_RDONLY);
 391         if (fd < 0)
 392                 return -1;
 393         len = strbuf_read(sb, fd, hint);
 394         close(fd);
 395         if (len < 0)
 396                 return -1;
 397
 398         return len;
 399 }
 400
 401 static int is_rfc3986_reserved(char ch)
 402 {
 403         switch (ch) {
 404                 case '!': case '*': case '\'': case '(': case ')': case ';':
 405                 case ':': case '@': case '&': case '=': case '+': case '$':
 406                 case ',': case '/': case '?': case '#': case '[': case ']':
 407                         return 1;
 408         }
 409         return 0;
 410 }
 411
 412 static int is_rfc3986_unreserved(char ch)
 413 {
 414         return isalnum(ch) ||
 415                 ch == '-' || ch == '_' || ch == '.' || ch == '~';
 416 }
 417
 418 void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 419                           int reserved)
 420 {
 421         strbuf_grow(sb, len);
 422         while (len--) {
 423                 char ch = *s++;
 424                 if (is_rfc3986_unreserved(ch) ||
 425                     (!reserved && is_rfc3986_reserved(ch)))
 426                         strbuf_addch(sb, ch);
 427                 else
 428                         strbuf_addf(sb, "%%%02x", ch);
 429         }
 430 }
 431
 432 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 433                              int reserved)
 434 {
 435         strbuf_add_urlencode(sb, s, strlen(s), reserved);
 436 }