#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdarg.h>
#include <stdbool.h>
#include <string.h>
#include <linux/zalloc.h>
#include <linux/kernel.h>
#include "intel-pt-log.h"
#include "intel-pt-insn-decoder.h"
#include "intel-pt-pkt-decoder.h"
#define MAX_LOG_NAME 256
#define DFLT_BUF_SZ (16 * 1024)
struct log_buf {
char *buf;
size_t buf_sz;
size_t head;
bool wrapped;
FILE *backend;
};
static FILE *f;
static char log_name[MAX_LOG_NAME];
bool intel_pt_enable_logging;
static bool intel_pt_dump_log_on_error;
static unsigned int intel_pt_log_on_error_size;
static struct log_buf log_buf;
void *intel_pt_log_fp(void)
{
return f;
}
void intel_pt_log_enable(bool dump_log_on_error, unsigned int log_on_error_size)
{
intel_pt_enable_logging = true;
intel_pt_dump_log_on_error = dump_log_on_error;
intel_pt_log_on_error_size = log_on_error_size;
}
void intel_pt_log_disable(void)
{
if (f)
fflush(f);
intel_pt_enable_logging = false;
}
void intel_pt_log_set_name(const char *name)
{
strncpy(log_name, name, MAX_LOG_NAME - 5);
strcat(log_name, ".log");
}
static void intel_pt_print_data(const unsigned char *buf, int len, uint64_t pos,
int indent)
{
int i;
for (i = 0; i < indent; i++)
fprintf(f, " ");
fprintf(f, " %08" PRIx64 ": ", pos);
for (i = 0; i < len; i++)
fprintf(f, " %02x", buf[i]);
for (; i < 16; i++)
fprintf(f, " ");
fprintf(f, " ");
}
static void intel_pt_print_no_data(uint64_t pos, int indent)
{
int i;
for (i = 0; i < indent; i++)
fprintf(f, " ");
fprintf(f, " %08" PRIx64 ": ", pos);
for (i = 0; i < 16; i++)
fprintf(f, " ");
fprintf(f, " ");
}
static ssize_t log_buf__write(void *cookie, const char *buf, size_t size)
{
struct log_buf *b = cookie;
size_t sz = size;
if (!b->buf)
return size;
while (sz) {
size_t space = b->buf_sz - b->head;
size_t n = min(space, sz);
memcpy(b->buf + b->head, buf, n);
sz -= n;
buf += n;
b->head += n;
if (sz && b->head >= b->buf_sz) {
b->head = 0;
b->wrapped = true;
}
}
return size;
}
static int log_buf__close(void *cookie)
{
struct log_buf *b = cookie;
zfree(&b->buf);
return 0;
}
static FILE *log_buf__open(struct log_buf *b, FILE *backend, unsigned int sz)
{
cookie_io_functions_t fns = {
.write = log_buf__write,
.close = log_buf__close,
};
FILE *file;
memset(b, 0, sizeof(*b));
b->buf_sz = sz;
b->buf = malloc(b->buf_sz);
b->backend = backend;
file = fopencookie(b, "a", fns);
if (!file)
zfree(&b->buf);
return file;
}
static bool remove_first_line(const char **p, size_t *n)
{
for (; *n && **p != '\n'; ++*p, --*n)
;
if (*n) {
*p += 1;
*n -= 1;
return true;
}
return false;
}
static void write_lines(const char *p, size_t n, FILE *fp, bool *remove_first)
{
if (*remove_first)
*remove_first = !remove_first_line(&p, &n);
fwrite(p, n, 1, fp);
}
static void log_buf__dump(struct log_buf *b)
{
bool remove_first = false;
if (!b->buf)
return;
fflush(f);
fprintf(b->backend, "Dumping debug log buffer\n");
if (b->wrapped) {
remove_first = true;
write_lines(b->buf + b->head, b->buf_sz - b->head, b->backend, &remove_first);
}
write_lines(b->buf, b->head, b->backend, &remove_first);
fprintf(b->backend, "End of debug log buffer dump\n");
b->head = 0;
b->wrapped = false;
}
void intel_pt_log_dump_buf(void)
{
log_buf__dump(&log_buf);
}
static int intel_pt_log_open(void)
{
if (!intel_pt_enable_logging)
return -1;
if (f)
return 0;
if (log_name[0])
f = fopen(log_name, "w+");
else
f = stdout;
if (f && intel_pt_dump_log_on_error)
f = log_buf__open(&log_buf, f, intel_pt_log_on_error_size);
if (!f) {
intel_pt_enable_logging = false;
return -1;
}
return 0;
}
void __intel_pt_log_packet(const struct intel_pt_pkt *packet, int pkt_len,
uint64_t pos, const unsigned char *buf)
{
char desc[INTEL_PT_PKT_DESC_MAX];
if (intel_pt_log_open())
return;
intel_pt_print_data(buf, pkt_len, pos, 0);
intel_pt_pkt_desc(packet, desc, INTEL_PT_PKT_DESC_MAX);
fprintf(f, "%s\n", desc);
}
void __intel_pt_log_insn(struct intel_pt_insn *intel_pt_insn, uint64_t ip)
{
char desc[INTEL_PT_INSN_DESC_MAX];
size_t len = intel_pt_insn->length;
if (intel_pt_log_open())
return;
if (len > INTEL_PT_INSN_BUF_SZ)
len = INTEL_PT_INSN_BUF_SZ;
intel_pt_print_data(intel_pt_insn->buf, len, ip, 8);
if (intel_pt_insn_desc(intel_pt_insn, desc, INTEL_PT_INSN_DESC_MAX) > 0)
fprintf(f, "%s\n", desc);
else
fprintf(f, "Bad instruction!\n");
}
void __intel_pt_log_insn_no_data(struct intel_pt_insn *intel_pt_insn,
uint64_t ip)
{
char desc[INTEL_PT_INSN_DESC_MAX];
if (intel_pt_log_open())
return;
intel_pt_print_no_data(ip, 8);
if (intel_pt_insn_desc(intel_pt_insn, desc, INTEL_PT_INSN_DESC_MAX) > 0)
fprintf(f, "%s\n", desc);
else
fprintf(f, "Bad instruction!\n");
}
void __intel_pt_log(const char *fmt, ...)
{
va_list args;
if (intel_pt_log_open())
return;
va_start(args, fmt);
vfprintf(f, fmt, args);
va_end(args);
}
