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