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#include "db.h"
uint16_t len(const char *s){
uint16_t l = -1;
while(s[++l]);
return l;
}
bool sameStr(const char *s1, const char *s2){
uint16_t i1 = 0, i2 = 0;
while(s1[i1] && s2[i2] && s1[i1] == s2[i2])
++i1, ++i2;
return !s1[i1] && !s2[i2];
}
// Auxiliary function for creating a lookup table of the haystack
// table[i] will be the number of shifts right until the next
// separator when checking position i
// Only really useful for this implementation of tags
static int *table(const char *y, int n, char sep){
int *tb = calloc(n, sizeof(int));
if(tb == NULL){
fprintf(stderr, "Error callocating array (table)");
exit(EXIT_FAILURE);
}
int lSep = n-1;
for(int i = n-1; i >= 0; --i){
if(y[i] == sep){
tb[i] = 1;
lSep = i;
}else if(y[i] != '\0'){
tb[i] = lSep-i;
}
}
return tb;
}
// Returns the position of ndl in tags, -1 if its not found
// A return of 0 means ndl occurs in tags starting in position 0
// Use 'if(strInTags(...) != -1)' when using this function
ssize_t strInTags(const char *tags, int n, const char *ndl, int m, char sep){
int *tb = table(tags, n, sep);
for(int i = 0; i < n; ){
int j = 0;
while(j < m && tags[i+j] == ndl[j]){
++j;
}
if(j == m){
return i;
}
if(tags[i+j] != ndl[j]){
i += tb[i];
}
}
return -1;
}
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