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/*
* Copyright 2006 Jon Loeliger
*/
#include "git-compat-util.h"
#include "interpolate.h"
void interp_set_entry(struct interp *table, int slot, const char *value)
{
char *oldval = table[slot].value;
char *newval = NULL;
if (oldval)
free(oldval);
if (value)
newval = xstrdup(value);
table[slot].value = newval;
}
void interp_clear_table(struct interp *table, int ninterps)
{
int i;
for (i = 0; i < ninterps; i++) {
interp_set_entry(table, i, NULL);
}
}
/*
* Convert a NUL-terminated string in buffer orig
* into the supplied buffer, result, whose length is reslen,
* performing substitutions on %-named sub-strings from
* the table, interps, with ninterps entries.
*
* Example interps:
* {
* { "%H", "example.org"},
* { "%port", "123"},
* { "%%", "%"},
* }
*
* Returns the length of the substituted string (not including the final \0).
* Like with snprintf, if the result is >= reslen, then it overflowed.
*/
unsigned long interpolate(char *result, unsigned long reslen,
const char *orig,
const struct interp *interps, int ninterps)
{
const char *src = orig;
char *dest = result;
unsigned long newlen = 0;
const char *name, *value;
unsigned long namelen, valuelen;
int i;
char c;
while ((c = *src)) {
if (c == '%') {
/* Try to match an interpolation string. */
for (i = 0; i < ninterps; i++) {
name = interps[i].name;
namelen = strlen(name);
if (strncmp(src, name, namelen) == 0)
break;
}
/* Check for valid interpolation. */
if (i < ninterps) {
value = interps[i].value;
valuelen = strlen(value);
if (newlen + valuelen < reslen) {
/* Substitute. */
memcpy(dest, value, valuelen);
dest += valuelen;
}
newlen += valuelen;
src += namelen;
continue;
}
}
/* Straight copy one non-interpolation character. */
if (newlen + 1 < reslen)
*dest++ = *src;
src++;
newlen++;
}
/* XXX: the previous loop always keep room for the ending NUL,
we just need to check if there was room for a NUL in the first place */
if (reslen > 0)
*dest = '\0';
return newlen;
}
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