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 void strbuf_tolower(struct strbuf *sb)
  95 {
  96         int i;
  97         for (i = 0; i < sb->len; i++)
  98                 sb->buf[i] = tolower(sb->buf[i]);
  99 }
 100
 101 struct strbuf **strbuf_split(const struct strbuf *sb, int delim)
 102 {
 103         int alloc = 2, pos = 0;
 104         char *n, *p;
 105         struct strbuf **ret;
 106         struct strbuf *t;
 107
 108         ret = xcalloc(alloc, sizeof(struct strbuf *));
 109         p = n = sb->buf;
 110         while (n < sb->buf + sb->len) {
 111                 int len;
 112                 n = memchr(n, delim, sb->len - (n - sb->buf));
 113                 if (pos + 1 >= alloc) {
 114                         alloc = alloc * 2;
 115                         ret = xrealloc(ret, sizeof(struct strbuf *) * alloc);
 116                 }
 117                 if (!n)
 118                         n = sb->buf + sb->len - 1;
 119                 len = n - p + 1;
 120                 t = xmalloc(sizeof(struct strbuf));
 121                 strbuf_init(t, len);
 122                 strbuf_add(t, p, len);
 123                 ret[pos] = t;
 124                 ret[++pos] = NULL;
 125                 p = ++n;
 126         }
 127         return ret;
 128 }
 129
 130 void strbuf_list_free(struct strbuf **sbs)
 131 {
 132         struct strbuf **s = sbs;
 133
 134         while (*s) {
 135                 strbuf_release(*s);
 136                 free(*s++);
 137         }
 138         free(sbs);
 139 }
 140
 141 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 142 {
 143         int len = a->len < b->len ? a->len: b->len;
 144         int cmp = memcmp(a->buf, b->buf, len);
 145         if (cmp)
 146                 return cmp;
 147         return a->len < b->len ? -1: a->len != b->len;
 148 }
 149
 150 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 151                                    const void *data, size_t dlen)
 152 {
 153         if (pos + len < pos)
 154                 die("you want to use way too much memory");
 155         if (pos > sb->len)
 156                 die("`pos' is too far after the end of the buffer");
 157         if (pos + len > sb->len)
 158                 die("`pos + len' is too far after the end of the buffer");
 159
 160         if (dlen >= len)
 161                 strbuf_grow(sb, dlen - len);
 162         memmove(sb->buf + pos + dlen,
 163                         sb->buf + pos + len,
 164                         sb->len - pos - len);
 165         memcpy(sb->buf + pos, data, dlen);
 166         strbuf_setlen(sb, sb->len + dlen - len);
 167 }
 168
 169 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 170 {
 171         strbuf_splice(sb, pos, 0, data, len);
 172 }
 173
 174 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 175 {
 176         strbuf_splice(sb, pos, len, NULL, 0);
 177 }
 178
 179 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 180 {
 181         strbuf_grow(sb, len);
 182         memcpy(sb->buf + sb->len, data, len);
 183         strbuf_setlen(sb, sb->len + len);
 184 }
 185
 186 void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 187 {
 188         strbuf_grow(sb, len);
 189         memcpy(sb->buf + sb->len, sb->buf + pos, len);
 190         strbuf_setlen(sb, sb->len + len);
 191 }
 192
 193 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 194 {
 195         int len;
 196         va_list ap;
 197
 198         if (!strbuf_avail(sb))
 199                 strbuf_grow(sb, 64);
 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 < 0)
 204                 die("your vsnprintf is broken");
 205         if (len > strbuf_avail(sb)) {
 206                 strbuf_grow(sb, len);
 207                 va_start(ap, fmt);
 208                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 209                 va_end(ap);
 210                 if (len > strbuf_avail(sb)) {
 211                         die("this should not happen, your snprintf is broken");
 212                 }
 213         }
 214         strbuf_setlen(sb, sb->len + len);
 215 }
 216
 217 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 218                    void *context)
 219 {
 220         for (;;) {
 221                 const char *percent;
 222                 size_t consumed;
 223
 224                 percent = strchrnul(format, '%');
 225                 strbuf_add(sb, format, percent - format);
 226                 if (!*percent)
 227                         break;
 228                 format = percent + 1;
 229
 230                 consumed = fn(sb, format, context);
 231                 if (consumed)
 232                         format += consumed;
 233                 else
 234                         strbuf_addch(sb, '%');
 235         }
 236 }
 237
 238 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 239                 void *context)
 240 {
 241         struct strbuf_expand_dict_entry *e = context;
 242         size_t len;
 243
 244         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 245                 if (!strncmp(placeholder, e->placeholder, len)) {
 246                         if (e->value)
 247                                 strbuf_addstr(sb, e->value);
 248                         return len;
 249                 }
 250         }
 251         return 0;
 252 }
 253
 254 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 255 {
 256         size_t res;
 257         size_t oldalloc = sb->alloc;
 258
 259         strbuf_grow(sb, size);
 260         res = fread(sb->buf + sb->len, 1, size, f);
 261         if (res > 0)
 262                 strbuf_setlen(sb, sb->len + res);
 263         else if (oldalloc == 0)
 264                 strbuf_release(sb);
 265         return res;
 266 }
 267
 268 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 269 {
 270         size_t oldlen = sb->len;
 271         size_t oldalloc = sb->alloc;
 272
 273         strbuf_grow(sb, hint ? hint : 8192);
 274         for (;;) {
 275                 ssize_t cnt;
 276
 277                 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 278                 if (cnt < 0) {
 279                         if (oldalloc == 0)
 280                                 strbuf_release(sb);
 281                         else
 282                                 strbuf_setlen(sb, oldlen);
 283                         return -1;
 284                 }
 285                 if (!cnt)
 286                         break;
 287                 sb->len += cnt;
 288                 strbuf_grow(sb, 8192);
 289         }
 290
 291         sb->buf[sb->len] = '\0';
 292         return sb->len - oldlen;
 293 }
 294
 295 #define STRBUF_MAXLINK (2*PATH_MAX)
 296
 297 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 298 {
 299         size_t oldalloc = sb->alloc;
 300
 301         if (hint < 32)
 302                 hint = 32;
 303
 304         while (hint < STRBUF_MAXLINK) {
 305                 int len;
 306
 307                 strbuf_grow(sb, hint);
 308                 len = readlink(path, sb->buf, hint);
 309                 if (len < 0) {
 310                         if (errno != ERANGE)
 311                                 break;
 312                 } else if (len < hint) {
 313                         strbuf_setlen(sb, len);
 314                         return 0;
 315                 }
 316
 317                 /* .. the buffer was too small - try again */
 318                 hint *= 2;
 319         }
 320         if (oldalloc == 0)
 321                 strbuf_release(sb);
 322         return -1;
 323 }
 324
 325 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 326 {
 327         int ch;
 328
 329         strbuf_grow(sb, 0);
 330         if (feof(fp))
 331                 return EOF;
 332
 333         strbuf_reset(sb);
 334         while ((ch = fgetc(fp)) != EOF) {
 335                 if (ch == term)
 336                         break;
 337                 strbuf_grow(sb, 1);
 338                 sb->buf[sb->len++] = ch;
 339         }
 340         if (ch == EOF && sb->len == 0)
 341                 return EOF;
 342
 343         sb->buf[sb->len] = '\0';
 344         return 0;
 345 }
 346
 347 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 348 {
 349         int fd, len;
 350
 351         fd = open(path, O_RDONLY);
 352         if (fd < 0)
 353                 return -1;
 354         len = strbuf_read(sb, fd, hint);
 355         close(fd);
 356         if (len < 0)
 357                 return -1;
 358
 359         return len;
 360 }
 361
 362 int strbuf_branchname(struct strbuf *sb, const char *name)
 363 {
 364         int len = strlen(name);
 365         if (interpret_branch_name(name, sb) == len)
 366                 return 0;
 367         strbuf_add(sb, name, len);
 368         return len;
 369 }
 370
 371 int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
 372 {
 373         strbuf_branchname(sb, name);
 374         strbuf_splice(sb, 0, 0, "refs/heads/", 11);
 375         return check_ref_format(sb->buf);
 376 }