3 #include <linux/kernel.h>
6 int prefixcmp(const char *str, const char *prefix)
8 for (; ; str++, prefix++)
11 else if (*str != *prefix)
12 return (unsigned char)*prefix - (unsigned char)*str;
16 * Used as the default ->buf value, so that people can always assume
17 * buf is non NULL and ->buf is NUL terminated even for a freshly
20 char strbuf_slopbuf[1];
22 int strbuf_init(struct strbuf *sb, ssize_t hint)
24 sb->alloc = sb->len = 0;
25 sb->buf = strbuf_slopbuf;
27 return strbuf_grow(sb, hint);
31 void strbuf_release(struct strbuf *sb)
39 char *strbuf_detach(struct strbuf *sb, size_t *sz)
41 char *res = sb->alloc ? sb->buf : NULL;
48 int strbuf_grow(struct strbuf *sb, size_t extra)
51 size_t nr = sb->len + extra + 1;
59 if (alloc_nr(sb->alloc) > nr)
60 nr = alloc_nr(sb->alloc);
63 * Note that sb->buf == strbuf_slopbuf if sb->alloc == 0, and it is
64 * a static variable. Thus we have to avoid passing it to realloc.
66 buf = realloc(sb->alloc ? sb->buf : NULL, nr * sizeof(*buf));
75 int strbuf_addch(struct strbuf *sb, int c)
77 int ret = strbuf_grow(sb, 1);
81 sb->buf[sb->len++] = c;
82 sb->buf[sb->len] = '\0';
86 int strbuf_add(struct strbuf *sb, const void *data, size_t len)
88 int ret = strbuf_grow(sb, len);
92 memcpy(sb->buf + sb->len, data, len);
93 return strbuf_setlen(sb, sb->len + len);
96 static int strbuf_addv(struct strbuf *sb, const char *fmt, va_list ap)
101 if (!strbuf_avail(sb)) {
102 ret = strbuf_grow(sb, 64);
107 va_copy(ap_saved, ap);
108 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
111 if (len > strbuf_avail(sb)) {
112 ret = strbuf_grow(sb, len);
115 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap_saved);
117 if (len > strbuf_avail(sb)) {
118 pr_debug("this should not happen, your vsnprintf is broken");
122 return strbuf_setlen(sb, sb->len + len);
125 int strbuf_addf(struct strbuf *sb, const char *fmt, ...)
131 ret = strbuf_addv(sb, fmt, ap);
136 ssize_t strbuf_read(struct strbuf *sb, int fd, ssize_t hint)
138 size_t oldlen = sb->len;
139 size_t oldalloc = sb->alloc;
142 ret = strbuf_grow(sb, hint ? hint : 8192);
149 cnt = read(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
154 strbuf_setlen(sb, oldlen);
160 ret = strbuf_grow(sb, 8192);
165 sb->buf[sb->len] = '\0';
166 return sb->len - oldlen;