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#include "strutil.h"
#include "arena.h" // struct arena, new
#include <assert.h> // assert
#include <stdarg.h> // va_*
#include <stdbool.h> // bool, false
#include <stdio.h> // vsnprintf
#include <string.h> // strlen, strncmp
int aprintf(struct arena *a, char **out, const char *fmt, ...) {
va_list ap;
va_start(ap, fmt);
int ret = vaprintf(a, out, fmt, ap);
va_end(ap);
return ret;
}
int vaprintf(struct arena *a, char **out, const char *fmt, va_list args) {
// Calculate size.
va_list tmp;
va_copy(tmp, args);
int size = vsnprintf(NULL, 0, fmt, args);
va_end(tmp);
// If e.g. the format string was broken, we cannot continue.
if (size < 0) {
return -1;
}
// Arena allocation cannot fail.
*out = new(a, char, size + 1);
int t = vsnprintf(*out, size + 1, fmt, args);
assert(t == size);
return size;
}
char *joinpath(struct arena *a, const char *path_a, const char *path_b) {
char *out;
int ret = aprintf(a, &out, "%s/%s", path_a, path_b);
assert(ret > 0 && "should be infallible");
return out;
}
bool endswith(const char *haystack, const char *needle) {
assert(haystack != NULL);
assert(needle != NULL);
size_t haystack_len = strlen(haystack);
size_t needle_len = strlen(needle);
if (needle_len > haystack_len) {
return false;
}
return strncmp(haystack + (haystack_len - needle_len), needle, needle_len) == 0;
}
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