Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 1 | #include "cache.h" |
Arnaldo Carvalho de Melo | e7f01d1 | 2012-03-14 12:29:29 -0300 | [diff] [blame] | 2 | #include <linux/kernel.h> |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 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 | |
Ingo Molnar | f37a291 | 2009-07-01 12:37:06 +0200 | [diff] [blame] | 20 | void strbuf_init(struct strbuf *sb, ssize_t hint) |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 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 | |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 45 | void strbuf_grow(struct strbuf *sb, size_t extra) |
| 46 | { |
| 47 | if (sb->len + extra + 1 <= sb->len) |
| 48 | die("you want to use way too much memory"); |
| 49 | if (!sb->alloc) |
| 50 | sb->buf = NULL; |
| 51 | ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc); |
| 52 | } |
| 53 | |
Arnaldo Carvalho de Melo | a41794c | 2010-05-18 18:29:23 -0300 | [diff] [blame] | 54 | static void strbuf_splice(struct strbuf *sb, size_t pos, size_t len, |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 55 | const void *data, size_t dlen) |
| 56 | { |
| 57 | if (pos + len < pos) |
| 58 | die("you want to use way too much memory"); |
| 59 | if (pos > sb->len) |
| 60 | die("`pos' is too far after the end of the buffer"); |
| 61 | if (pos + len > sb->len) |
| 62 | die("`pos + len' is too far after the end of the buffer"); |
| 63 | |
| 64 | if (dlen >= len) |
| 65 | strbuf_grow(sb, dlen - len); |
| 66 | memmove(sb->buf + pos + dlen, |
| 67 | sb->buf + pos + len, |
| 68 | sb->len - pos - len); |
| 69 | memcpy(sb->buf + pos, data, dlen); |
| 70 | strbuf_setlen(sb, sb->len + dlen - len); |
| 71 | } |
| 72 | |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 73 | void strbuf_remove(struct strbuf *sb, size_t pos, size_t len) |
| 74 | { |
| 75 | strbuf_splice(sb, pos, len, NULL, 0); |
| 76 | } |
| 77 | |
| 78 | void strbuf_add(struct strbuf *sb, const void *data, size_t len) |
| 79 | { |
| 80 | strbuf_grow(sb, len); |
| 81 | memcpy(sb->buf + sb->len, data, len); |
| 82 | strbuf_setlen(sb, sb->len + len); |
| 83 | } |
| 84 | |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 85 | void strbuf_addf(struct strbuf *sb, const char *fmt, ...) |
| 86 | { |
| 87 | int len; |
| 88 | va_list ap; |
| 89 | |
| 90 | if (!strbuf_avail(sb)) |
| 91 | strbuf_grow(sb, 64); |
| 92 | va_start(ap, fmt); |
Arnaldo Carvalho de Melo | e7f01d1 | 2012-03-14 12:29:29 -0300 | [diff] [blame] | 93 | len = vscnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap); |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 94 | va_end(ap); |
| 95 | if (len < 0) |
Arnaldo Carvalho de Melo | e7f01d1 | 2012-03-14 12:29:29 -0300 | [diff] [blame] | 96 | die("your vscnprintf is broken"); |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 97 | if (len > strbuf_avail(sb)) { |
| 98 | strbuf_grow(sb, len); |
| 99 | va_start(ap, fmt); |
Arnaldo Carvalho de Melo | e7f01d1 | 2012-03-14 12:29:29 -0300 | [diff] [blame] | 100 | len = vscnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap); |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 101 | va_end(ap); |
| 102 | if (len > strbuf_avail(sb)) { |
| 103 | die("this should not happen, your snprintf is broken"); |
| 104 | } |
| 105 | } |
| 106 | strbuf_setlen(sb, sb->len + len); |
| 107 | } |
| 108 | |
Ingo Molnar | f37a291 | 2009-07-01 12:37:06 +0200 | [diff] [blame] | 109 | ssize_t strbuf_read(struct strbuf *sb, int fd, ssize_t hint) |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 110 | { |
| 111 | size_t oldlen = sb->len; |
| 112 | size_t oldalloc = sb->alloc; |
| 113 | |
| 114 | strbuf_grow(sb, hint ? hint : 8192); |
| 115 | for (;;) { |
| 116 | ssize_t cnt; |
| 117 | |
| 118 | cnt = read(fd, sb->buf + sb->len, sb->alloc - sb->len - 1); |
| 119 | if (cnt < 0) { |
| 120 | if (oldalloc == 0) |
| 121 | strbuf_release(sb); |
| 122 | else |
| 123 | strbuf_setlen(sb, oldlen); |
| 124 | return -1; |
| 125 | } |
| 126 | if (!cnt) |
| 127 | break; |
| 128 | sb->len += cnt; |
| 129 | strbuf_grow(sb, 8192); |
| 130 | } |
| 131 | |
| 132 | sb->buf[sb->len] = '\0'; |
| 133 | return sb->len - oldlen; |
| 134 | } |