radare2/libr/util/cache.c
2015-12-08 13:24:21 +01:00

76 lines
1.7 KiB
C

/* radare - LGPL - Copyright 2013-2015 - pancake */
// XXX: should use the same code as libr/io/cache.c
// one malloc per write
#include <r_util.h>
// TODO: optimize reallocs.. store RBuffer info.. wait. extend r_buf_ for that?
R_API RCache *r_cache_new() {
RCache *c = R_NEW (RCache);
c->buf = NULL;
c->base = 0;
c->len = 0;
return c;
}
R_API void r_cache_free(RCache *c) {
free (c->buf);
free (c);
}
R_API const ut8 *r_cache_get(RCache *c, ut64 addr, int *len) {
if (!c->buf)
return NULL;
if (len) *len = c->base - addr;
if (addr < c->base)
return NULL;
if (addr > (c->base + c->len))
return NULL;
if (len) *len = c->len - (addr - c->base);
//eprintf ("4 - %d\n", (addr-c->base));
return c->buf + (addr - c->base);
}
R_API int r_cache_set(RCache *c, ut64 addr, const ut8 *buf, int len) {
if (c->buf == NULL) {
c->buf = malloc (len);
if (!c->buf) return 0;
memcpy (c->buf, buf, len);
c->base = addr;
c->len = len;
} else if (addr < c->base) {
ut8 *b;
int baselen = (c->base - addr);
int newlen = baselen + ((len > c->len)? len: c->base);
// XXX expensive heap usage. must simplify
b = malloc (newlen);
if (!b) return 0;
memset (b, 0xff, newlen);
memcpy (b + baselen, c->buf, c->len);
memcpy (b, buf, len);
free (c->buf);
c->buf = b;
c->base = addr;
c->len = newlen;
} else if ((addr + len) > (c->base + c->len)) {
ut8 *b;
int baselen = (addr - c->base);
int newlen = baselen + len;
b = realloc (c->buf, newlen);
if (!b) return 0;
memcpy (b + baselen, buf, len);
c->buf = b;
c->len = newlen;
} else {
memcpy (c->buf, buf, len);
}
return c->len;
}
R_API void r_cache_flush(RCache *c) {
c->base = 0;
c->len = 0;
free (c->buf);
c->buf = NULL;
}