180 строки
3.4 KiB
C
180 строки
3.4 KiB
C
#include <linux/compiler.h>
|
|
#include <linux/kernel.h>
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
#include <unistd.h>
|
|
#include <string.h>
|
|
|
|
#include "data.h"
|
|
#include "util.h"
|
|
#include "debug.h"
|
|
|
|
static bool check_pipe(struct perf_data_file *file)
|
|
{
|
|
struct stat st;
|
|
bool is_pipe = false;
|
|
int fd = perf_data_file__is_read(file) ?
|
|
STDIN_FILENO : STDOUT_FILENO;
|
|
|
|
if (!file->path) {
|
|
if (!fstat(fd, &st) && S_ISFIFO(st.st_mode))
|
|
is_pipe = true;
|
|
} else {
|
|
if (!strcmp(file->path, "-"))
|
|
is_pipe = true;
|
|
}
|
|
|
|
if (is_pipe)
|
|
file->fd = fd;
|
|
|
|
return file->is_pipe = is_pipe;
|
|
}
|
|
|
|
static int check_backup(struct perf_data_file *file)
|
|
{
|
|
struct stat st;
|
|
|
|
if (!stat(file->path, &st) && st.st_size) {
|
|
/* TODO check errors properly */
|
|
char oldname[PATH_MAX];
|
|
snprintf(oldname, sizeof(oldname), "%s.old",
|
|
file->path);
|
|
unlink(oldname);
|
|
rename(file->path, oldname);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int open_file_read(struct perf_data_file *file)
|
|
{
|
|
struct stat st;
|
|
int fd;
|
|
char sbuf[STRERR_BUFSIZE];
|
|
|
|
fd = open(file->path, O_RDONLY);
|
|
if (fd < 0) {
|
|
int err = errno;
|
|
|
|
pr_err("failed to open %s: %s", file->path,
|
|
strerror_r(err, sbuf, sizeof(sbuf)));
|
|
if (err == ENOENT && !strcmp(file->path, "perf.data"))
|
|
pr_err(" (try 'perf record' first)");
|
|
pr_err("\n");
|
|
return -err;
|
|
}
|
|
|
|
if (fstat(fd, &st) < 0)
|
|
goto out_close;
|
|
|
|
if (!file->force && st.st_uid && (st.st_uid != geteuid())) {
|
|
pr_err("File %s not owned by current user or root (use -f to override)\n",
|
|
file->path);
|
|
goto out_close;
|
|
}
|
|
|
|
if (!st.st_size) {
|
|
pr_info("zero-sized file (%s), nothing to do!\n",
|
|
file->path);
|
|
goto out_close;
|
|
}
|
|
|
|
file->size = st.st_size;
|
|
return fd;
|
|
|
|
out_close:
|
|
close(fd);
|
|
return -1;
|
|
}
|
|
|
|
static int open_file_write(struct perf_data_file *file)
|
|
{
|
|
int fd;
|
|
char sbuf[STRERR_BUFSIZE];
|
|
|
|
if (check_backup(file))
|
|
return -1;
|
|
|
|
fd = open(file->path, O_CREAT|O_RDWR|O_TRUNC, S_IRUSR|S_IWUSR);
|
|
|
|
if (fd < 0)
|
|
pr_err("failed to open %s : %s\n", file->path,
|
|
strerror_r(errno, sbuf, sizeof(sbuf)));
|
|
|
|
return fd;
|
|
}
|
|
|
|
static int open_file(struct perf_data_file *file)
|
|
{
|
|
int fd;
|
|
|
|
fd = perf_data_file__is_read(file) ?
|
|
open_file_read(file) : open_file_write(file);
|
|
|
|
file->fd = fd;
|
|
return fd < 0 ? -1 : 0;
|
|
}
|
|
|
|
int perf_data_file__open(struct perf_data_file *file)
|
|
{
|
|
if (check_pipe(file))
|
|
return 0;
|
|
|
|
if (!file->path)
|
|
file->path = "perf.data";
|
|
|
|
return open_file(file);
|
|
}
|
|
|
|
void perf_data_file__close(struct perf_data_file *file)
|
|
{
|
|
close(file->fd);
|
|
}
|
|
|
|
ssize_t perf_data_file__write(struct perf_data_file *file,
|
|
void *buf, size_t size)
|
|
{
|
|
return writen(file->fd, buf, size);
|
|
}
|
|
|
|
int perf_data_file__switch(struct perf_data_file *file,
|
|
const char *postfix,
|
|
size_t pos, bool at_exit)
|
|
{
|
|
char *new_filepath;
|
|
int ret;
|
|
|
|
if (check_pipe(file))
|
|
return -EINVAL;
|
|
if (perf_data_file__is_read(file))
|
|
return -EINVAL;
|
|
|
|
if (asprintf(&new_filepath, "%s.%s", file->path, postfix) < 0)
|
|
return -ENOMEM;
|
|
|
|
/*
|
|
* Only fire a warning, don't return error, continue fill
|
|
* original file.
|
|
*/
|
|
if (rename(file->path, new_filepath))
|
|
pr_warning("Failed to rename %s to %s\n", file->path, new_filepath);
|
|
|
|
if (!at_exit) {
|
|
close(file->fd);
|
|
ret = perf_data_file__open(file);
|
|
if (ret < 0)
|
|
goto out;
|
|
|
|
if (lseek(file->fd, pos, SEEK_SET) == (off_t)-1) {
|
|
ret = -errno;
|
|
pr_debug("Failed to lseek to %zu: %s",
|
|
pos, strerror(errno));
|
|
goto out;
|
|
}
|
|
}
|
|
ret = file->fd;
|
|
out:
|
|
free(new_filepath);
|
|
return ret;
|
|
}
|