siovec_search.c (1011B)
1 /* ISC license. */ 2 3 #include <string.h> 4 #include <sys/uio.h> 5 #include <skalibs/posixplz.h> 6 #include <skalibs/siovec.h> 7 8 size_t siovec_search (struct iovec const *v, unsigned int n, char const *needle, size_t nlen) 9 { 10 size_t vlen = siovec_len(v, n) ; 11 size_t w = 0 ; 12 unsigned int i = 0 ; 13 for (; i < n ; i++) 14 { 15 char *p = memmem(v[i].iov_base, v[i].iov_len, needle, nlen) ; 16 if (p) return w + (p - (char *)v[i].iov_base) ; 17 if (i < n-1 && nlen > 1 && v[i].iov_len) 18 { 19 size_t prelen = v[i].iov_len < nlen ? v[i].iov_len : nlen ; 20 size_t postlen = vlen - w - v[i].iov_len < nlen ? vlen - w - v[i].iov_len : nlen ; 21 char buf[prelen + postlen - 2] ; 22 memcpy(buf, (char *)v[i].iov_base + v[i].iov_len - prelen + 1, prelen - 1) ; 23 siovec_gather(v + i + 1, n - 1 - i, buf + prelen - 1, postlen - 1) ; 24 p = memmem(buf, prelen + postlen - 2, needle, nlen) ; 25 if (p) return w + v[i].iov_len - prelen + 1 + (p - buf) ; 26 } 27 w += v[i].iov_len ; 28 } 29 return w ; 30 }