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 cmp;
 143         if (a->len < b->len) {
 144                 cmp = memcmp(a->buf, b->buf, a->len);
 145                 return cmp ? cmp : -1;
 146         } else {
 147                 cmp = memcmp(a->buf, b->buf, b->len);
 148                 return cmp ? cmp : a->len != b->len;
 149         }
 150 }
 151
 152 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 153                                    const void *data, size_t dlen)
 154 {
 155         if (pos + len < pos)
 156                 die("you want to use way too much memory");
 157         if (pos > sb->len)
 158                 die("`pos' is too far after the end of the buffer");
 159         if (pos + len > sb->len)
 160                 die("`pos + len' is too far after the end of the buffer");
 161
 162         if (dlen >= len)
 163                 strbuf_grow(sb, dlen - len);
 164         memmove(sb->buf + pos + dlen,
 165                         sb->buf + pos + len,
 166                         sb->len - pos - len);
 167         memcpy(sb->buf + pos, data, dlen);
 168         strbuf_setlen(sb, sb->len + dlen - len);
 169 }
 170
 171 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 172 {
 173         strbuf_splice(sb, pos, 0, data, len);
 174 }
 175
 176 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 177 {
 178         strbuf_splice(sb, pos, len, NULL, 0);
 179 }
 180
 181 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 182 {
 183         strbuf_grow(sb, len);
 184         memcpy(sb->buf + sb->len, data, len);
 185         strbuf_setlen(sb, sb->len + len);
 186 }
 187
 188 void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 189 {
 190         strbuf_grow(sb, len);
 191         memcpy(sb->buf + sb->len, sb->buf + pos, len);
 192         strbuf_setlen(sb, sb->len + len);
 193 }
 194
 195 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 196 {
 197         int len;
 198         va_list ap;
 199
 200         if (!strbuf_avail(sb))
 201                 strbuf_grow(sb, 64);
 202         va_start(ap, fmt);
 203         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 204         va_end(ap);
 205         if (len < 0)
 206                 die("your vsnprintf is broken");
 207         if (len > strbuf_avail(sb)) {
 208                 strbuf_grow(sb, len);
 209                 va_start(ap, fmt);
 210                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 211                 va_end(ap);
 212                 if (len > strbuf_avail(sb)) {
 213                         die("this should not happen, your snprintf is broken");
 214                 }
 215         }
 216         strbuf_setlen(sb, sb->len + len);
 217 }
 218
 219 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 220                    void *context)
 221 {
 222         for (;;) {
 223                 const char *percent;
 224                 size_t consumed;
 225
 226                 percent = strchrnul(format, '%');
 227                 strbuf_add(sb, format, percent - format);
 228                 if (!*percent)
 229                         break;
 230                 format = percent + 1;
 231
 232                 consumed = fn(sb, format, context);
 233                 if (consumed)
 234                         format += consumed;
 235                 else
 236                         strbuf_addch(sb, '%');
 237         }
 238 }
 239
 240 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 241                 void *context)
 242 {
 243         struct strbuf_expand_dict_entry *e = context;
 244         size_t len;
 245
 246         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 247                 if (!strncmp(placeholder, e->placeholder, len)) {
 248                         if (e->value)
 249                                 strbuf_addstr(sb, e->value);
 250                         return len;
 251                 }
 252         }
 253         return 0;
 254 }
 255
 256 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 257 {
 258         size_t res;
 259         size_t oldalloc = sb->alloc;
 260
 261         strbuf_grow(sb, size);
 262         res = fread(sb->buf + sb->len, 1, size, f);
 263         if (res > 0)
 264                 strbuf_setlen(sb, sb->len + res);
 265         else if (res < 0 && oldalloc == 0)
 266                 strbuf_release(sb);
 267         return res;
 268 }
 269
 270 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 271 {
 272         size_t oldlen = sb->len;
 273         size_t oldalloc = sb->alloc;
 274
 275         strbuf_grow(sb, hint ? hint : 8192);
 276         for (;;) {
 277                 ssize_t cnt;
 278
 279                 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 280                 if (cnt < 0) {
 281                         if (oldalloc == 0)
 282                                 strbuf_release(sb);
 283                         else
 284                                 strbuf_setlen(sb, oldlen);
 285                         return -1;
 286                 }
 287                 if (!cnt)
 288                         break;
 289                 sb->len += cnt;
 290                 strbuf_grow(sb, 8192);
 291         }
 292
 293         sb->buf[sb->len] = '\0';
 294         return sb->len - oldlen;
 295 }
 296
 297 #define STRBUF_MAXLINK (2*PATH_MAX)
 298
 299 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 300 {
 301         size_t oldalloc = sb->alloc;
 302
 303         if (hint < 32)
 304                 hint = 32;
 305
 306         while (hint < STRBUF_MAXLINK) {
 307                 int len;
 308
 309                 strbuf_grow(sb, hint);
 310                 len = readlink(path, sb->buf, hint);
 311                 if (len < 0) {
 312                         if (errno != ERANGE)
 313                                 break;
 314                 } else if (len < hint) {
 315                         strbuf_setlen(sb, len);
 316                         return 0;
 317                 }
 318
 319                 /* .. the buffer was too small - try again */
 320                 hint *= 2;
 321         }
 322         if (oldalloc == 0)
 323                 strbuf_release(sb);
 324         return -1;
 325 }
 326
 327 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 328 {
 329         int ch;
 330
 331         strbuf_grow(sb, 0);
 332         if (feof(fp))
 333                 return EOF;
 334
 335         strbuf_reset(sb);
 336         while ((ch = fgetc(fp)) != EOF) {
 337                 if (ch == term)
 338                         break;
 339                 strbuf_grow(sb, 1);
 340                 sb->buf[sb->len++] = ch;
 341         }
 342         if (ch == EOF && sb->len == 0)
 343                 return EOF;
 344
 345         sb->buf[sb->len] = '\0';
 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 }