1e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng#include "cache.h" 2e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng#include <linux/kernel.h> 3e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 4e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Chengint prefixcmp(const char *str, const char *prefix) 5e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng{ 6e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng for (; ; str++, prefix++) 7e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (!*prefix) 8e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng return 0; 9e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng else if (*str != *prefix) 10e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng return (unsigned char)*prefix - (unsigned char)*str; 11e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng} 12e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 13e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng/* 14e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng * Used as the default ->buf value, so that people can always assume 15e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng * buf is non NULL and ->buf is NUL terminated even for a freshly 16e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng * initialized strbuf. 17e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng */ 18e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Chengchar strbuf_slopbuf[1]; 19e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 20e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Chengvoid strbuf_init(struct strbuf *sb, ssize_t hint) 21e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng{ 22e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng sb->alloc = sb->len = 0; 23e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng sb->buf = strbuf_slopbuf; 24e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (hint) 25e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_grow(sb, hint); 26e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng} 27e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 28e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Chengvoid strbuf_release(struct strbuf *sb) 29e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng{ 30e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (sb->alloc) { 31e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng free(sb->buf); 32e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_init(sb, 0); 33e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng } 34e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng} 35e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 36e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Chengchar *strbuf_detach(struct strbuf *sb, size_t *sz) 37e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng{ 38e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng char *res = sb->alloc ? sb->buf : NULL; 39e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (sz) 40e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng *sz = sb->len; 41e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_init(sb, 0); 42e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng return res; 43e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng} 44e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 45e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Chengvoid strbuf_grow(struct strbuf *sb, size_t extra) 46e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng{ 47e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (sb->len + extra + 1 <= sb->len) 48e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng die("you want to use way too much memory"); 49e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (!sb->alloc) 50e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng sb->buf = NULL; 51e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc); 52e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng} 53e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 54e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Chengstatic void strbuf_splice(struct strbuf *sb, size_t pos, size_t len, 55e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng const void *data, size_t dlen) 56e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng{ 57e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (pos + len < pos) 58e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng die("you want to use way too much memory"); 59e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (pos > sb->len) 60e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng die("`pos' is too far after the end of the buffer"); 61e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (pos + len > sb->len) 62e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng die("`pos + len' is too far after the end of the buffer"); 63e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 64e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (dlen >= len) 65e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_grow(sb, dlen - len); 66e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng memmove(sb->buf + pos + dlen, 67e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng sb->buf + pos + len, 68e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng sb->len - pos - len); 69e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng memcpy(sb->buf + pos, data, dlen); 70e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_setlen(sb, sb->len + dlen - len); 71e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng} 72e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 73e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Chengvoid strbuf_remove(struct strbuf *sb, size_t pos, size_t len) 74e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng{ 75e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_splice(sb, pos, len, NULL, 0); 76e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng} 77e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 78e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Chengvoid strbuf_add(struct strbuf *sb, const void *data, size_t len) 79e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng{ 80e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_grow(sb, len); 81e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng memcpy(sb->buf + sb->len, data, len); 82e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_setlen(sb, sb->len + len); 83e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng} 84e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 85e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Chengvoid strbuf_addf(struct strbuf *sb, const char *fmt, ...) 86e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng{ 87e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng int len; 88e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng va_list ap; 89e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 90e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (!strbuf_avail(sb)) 91e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_grow(sb, 64); 92e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng va_start(ap, fmt); 93e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap); 94e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng va_end(ap); 95e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (len < 0) 96e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng die("your vsnprintf is broken"); 97e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (len > strbuf_avail(sb)) { 98e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_grow(sb, len); 99e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng va_start(ap, fmt); 100e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap); 101e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng va_end(ap); 102e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (len > strbuf_avail(sb)) { 103e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng die("this should not happen, your vsnprintf is broken"); 104e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng } 105e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng } 106e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_setlen(sb, sb->len + len); 107e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng} 108e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 109e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Chengssize_t strbuf_read(struct strbuf *sb, int fd, ssize_t hint) 110e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng{ 111e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng size_t oldlen = sb->len; 112e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng size_t oldalloc = sb->alloc; 113e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 114e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_grow(sb, hint ? hint : 8192); 115e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng for (;;) { 116e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng ssize_t cnt; 117e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 118e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng cnt = read(fd, sb->buf + sb->len, sb->alloc - sb->len - 1); 119e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (cnt < 0) { 120e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (oldalloc == 0) 121e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_release(sb); 122e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng else 123e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_setlen(sb, oldlen); 124e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng return -1; 125e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng } 126e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng if (!cnt) 127e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng break; 128e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng sb->len += cnt; 129e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng strbuf_grow(sb, 8192); 130e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng } 131e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng 132e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng sb->buf[sb->len] = '\0'; 133e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng return sb->len - oldlen; 134e6e8a0bd7cffcc9ae2e0e75546fb12a19213d4aeBen Cheng} 135