strbuf.c

   1 #include "cache.h"
   2
   3 int prefixcmp(const char *str, const char *prefix)
   4 {
   5         for (; ; str++, prefix++)
   6                 if (!*prefix)
   7                         return 0;
   8                 else if (*str != *prefix)
   9                         return (unsigned char)*prefix - (unsigned char)*str;
  10 }
  11
  12 /*
  13  * Used as the default ->buf value, so that people can always assume
  14  * buf is non NULL and ->buf is NUL terminated even for a freshly
  15  * initialized strbuf.
  16  */
  17 char strbuf_slopbuf[1];
  18
  19 void strbuf_init(struct strbuf *sb, size_t hint)
  20 {
  21         sb->alloc = sb->len = 0;
  22         sb->buf = strbuf_slopbuf;
  23         if (hint)
  24                 strbuf_grow(sb, hint);
  25 }
  26
  27 void strbuf_release(struct strbuf *sb)
  28 {
  29         if (sb->alloc) {
  30                 free(sb->buf);
  31                 strbuf_init(sb, 0);
  32         }
  33 }
  34
  35 char *strbuf_detach(struct strbuf *sb, size_t *sz)
  36 {
  37         char *res = sb->alloc ? sb->buf : NULL;
  38         if (sz)
  39                 *sz = sb->len;
  40         strbuf_init(sb, 0);
  41         return res;
  42 }
  43
  44 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
  45 {
  46         strbuf_release(sb);
  47         sb->buf   = buf;
  48         sb->len   = len;
  49         sb->alloc = alloc;
  50         strbuf_grow(sb, 0);
  51         sb->buf[sb->len] = '\0';
  52 }
  53
  54 void strbuf_grow(struct strbuf *sb, size_t extra)
  55 {
  56         if (sb->len + extra + 1 <= sb->len)
  57                 die("you want to use way too much memory");
  58         if (!sb->alloc)
  59                 sb->buf = NULL;
  60         ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
  61 }
  62
  63 void strbuf_trim(struct strbuf *sb)
  64 {
  65         char *b = sb->buf;
  66         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
  67                 sb->len--;
  68         while (sb->len > 0 && isspace(*b)) {
  69                 b++;
  70                 sb->len--;
  71         }
  72         memmove(sb->buf, b, sb->len);
  73         sb->buf[sb->len] = '\0';
  74 }
  75 void strbuf_rtrim(struct strbuf *sb)
  76 {
  77         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
  78                 sb->len--;
  79         sb->buf[sb->len] = '\0';
  80 }
  81
  82 void strbuf_ltrim(struct strbuf *sb)
  83 {
  84         char *b = sb->buf;
  85         while (sb->len > 0 && isspace(*b)) {
  86                 b++;
  87                 sb->len--;
  88         }
  89         memmove(sb->buf, b, sb->len);
  90         sb->buf[sb->len] = '\0';
  91 }
  92
  93 void strbuf_tolower(struct strbuf *sb)
  94 {
  95         int i;
  96         for (i = 0; i < sb->len; i++)
  97                 sb->buf[i] = tolower(sb->buf[i]);
  98 }
  99
 100 struct strbuf **strbuf_split(const struct strbuf *sb, int delim)
 101 {
 102         int alloc = 2, pos = 0;
 103         char *n, *p;
 104         struct strbuf **ret;
 105         struct strbuf *t;
 106
 107         ret = xcalloc(alloc, sizeof(struct strbuf *));
 108         p = n = sb->buf;
 109         while (n < sb->buf + sb->len) {
 110                 int len;
 111                 n = memchr(n, delim, sb->len - (n - sb->buf));
 112                 if (pos + 1 >= alloc) {
 113                         alloc = alloc * 2;
 114                         ret = xrealloc(ret, sizeof(struct strbuf *) * alloc);
 115                 }
 116                 if (!n)
 117                         n = sb->buf + sb->len - 1;
 118                 len = n - p + 1;
 119                 t = xmalloc(sizeof(struct strbuf));
 120                 strbuf_init(t, len);
 121                 strbuf_add(t, p, len);
 122                 ret[pos] = t;
 123                 ret[++pos] = NULL;
 124                 p = ++n;
 125         }
 126         return ret;
 127 }
 128
 129 void strbuf_list_free(struct strbuf **sbs)
 130 {
 131         struct strbuf **s = sbs;
 132
 133         while (*s) {
 134                 strbuf_release(*s);
 135                 free(*s++);
 136         }
 137         free(sbs);
 138 }
 139
 140 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 141 {
 142         int len = a->len < b->len ? a->len: b->len;
 143         int cmp = memcmp(a->buf, b->buf, len);
 144         if (cmp)
 145                 return cmp;
 146         return a->len < b->len ? -1: a->len != b->len;
 147 }
 148
 149 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 150                                    const void *data, size_t dlen)
 151 {
 152         if (pos + len < pos)
 153                 die("you want to use way too much memory");
 154         if (pos > sb->len)
 155                 die("`pos' is too far after the end of the buffer");
 156         if (pos + len > sb->len)
 157                 die("`pos + len' is too far after the end of the buffer");
 158
 159         if (dlen >= len)
 160                 strbuf_grow(sb, dlen - len);
 161         memmove(sb->buf + pos + dlen,
 162                         sb->buf + pos + len,
 163                         sb->len - pos - len);
 164         memcpy(sb->buf + pos, data, dlen);
 165         strbuf_setlen(sb, sb->len + dlen - len);
 166 }
 167
 168 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 169 {
 170         strbuf_splice(sb, pos, 0, data, len);
 171 }
 172
 173 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 174 {
 175         strbuf_splice(sb, pos, len, NULL, 0);
 176 }
 177
 178 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 179 {
 180         strbuf_grow(sb, len);
 181         memcpy(sb->buf + sb->len, data, len);
 182         strbuf_setlen(sb, sb->len + len);
 183 }
 184
 185 void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 186 {
 187         strbuf_grow(sb, len);
 188         memcpy(sb->buf + sb->len, sb->buf + pos, len);
 189         strbuf_setlen(sb, sb->len + len);
 190 }
 191
 192 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 193 {
 194         int len;
 195         va_list ap;
 196
 197         if (!strbuf_avail(sb))
 198                 strbuf_grow(sb, 64);
 199         va_start(ap, fmt);
 200         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 201         va_end(ap);
 202         if (len < 0)
 203                 die("your vsnprintf is broken");
 204         if (len > strbuf_avail(sb)) {
 205                 strbuf_grow(sb, len);
 206                 va_start(ap, fmt);
 207                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 208                 va_end(ap);
 209                 if (len > strbuf_avail(sb)) {
 210                         die("this should not happen, your snprintf is broken");
 211                 }
 212         }
 213         strbuf_setlen(sb, sb->len + len);
 214 }
 215
 216 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 217                    void *context)
 218 {
 219         for (;;) {
 220                 const char *percent;
 221                 size_t consumed;
 222
 223                 percent = strchrnul(format, '%');
 224                 strbuf_add(sb, format, percent - format);
 225                 if (!*percent)
 226                         break;
 227                 format = percent + 1;
 228
 229                 consumed = fn(sb, format, context);
 230                 if (consumed)
 231                         format += consumed;
 232                 else
 233                         strbuf_addch(sb, '%');
 234         }
 235 }
 236
 237 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 238                 void *context)
 239 {
 240         struct strbuf_expand_dict_entry *e = context;
 241         size_t len;
 242
 243         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 244                 if (!strncmp(placeholder, e->placeholder, len)) {
 245                         if (e->value)
 246                                 strbuf_addstr(sb, e->value);
 247                         return len;
 248                 }
 249         }
 250         return 0;
 251 }
 252
 253 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 254 {
 255         size_t res;
 256         size_t oldalloc = sb->alloc;
 257
 258         strbuf_grow(sb, size);
 259         res = fread(sb->buf + sb->len, 1, size, f);
 260         if (res > 0)
 261                 strbuf_setlen(sb, sb->len + res);
 262         else if (res < 0 && oldalloc == 0)
 263                 strbuf_release(sb);
 264         return res;
 265 }
 266
 267 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 268 {
 269         size_t oldlen = sb->len;
 270         size_t oldalloc = sb->alloc;
 271
 272         strbuf_grow(sb, hint ? hint : 8192);
 273         for (;;) {
 274                 ssize_t cnt;
 275
 276                 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 277                 if (cnt < 0) {
 278                         if (oldalloc == 0)
 279                                 strbuf_release(sb);
 280                         else
 281                                 strbuf_setlen(sb, oldlen);
 282                         return -1;
 283                 }
 284                 if (!cnt)
 285                         break;
 286                 sb->len += cnt;
 287                 strbuf_grow(sb, 8192);
 288         }
 289
 290         sb->buf[sb->len] = '\0';
 291         return sb->len - oldlen;
 292 }
 293
 294 #define STRBUF_MAXLINK (2*PATH_MAX)
 295
 296 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 297 {
 298         size_t oldalloc = sb->alloc;
 299
 300         if (hint < 32)
 301                 hint = 32;
 302
 303         while (hint < STRBUF_MAXLINK) {
 304                 int len;
 305
 306                 strbuf_grow(sb, hint);
 307                 len = readlink(path, sb->buf, hint);
 308                 if (len < 0) {
 309                         if (errno != ERANGE)
 310                                 break;
 311                 } else if (len < hint) {
 312                         strbuf_setlen(sb, len);
 313                         return 0;
 314                 }
 315
 316                 /* .. the buffer was too small - try again */
 317                 hint *= 2;
 318         }
 319         if (oldalloc == 0)
 320                 strbuf_release(sb);
 321         return -1;
 322 }
 323
 324 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 325 {
 326         int ch;
 327
 328         strbuf_grow(sb, 0);
 329         if (feof(fp))
 330                 return EOF;
 331
 332         strbuf_reset(sb);
 333         while ((ch = fgetc(fp)) != EOF) {
 334                 if (ch == term)
 335                         break;
 336                 strbuf_grow(sb, 1);
 337                 sb->buf[sb->len++] = ch;
 338         }
 339         if (ch == EOF && sb->len == 0)
 340                 return EOF;
 341
 342         sb->buf[sb->len] = '\0';
 343         return 0;
 344 }
 345
 346 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 347 {
 348         int fd, len;
 349
 350         fd = open(path, O_RDONLY);
 351         if (fd < 0)
 352                 return -1;
 353         len = strbuf_read(sb, fd, hint);
 354         close(fd);
 355         if (len < 0)
 356                 return -1;
 357
 358         return len;
 359 }