261 lines
8.4 KiB
C
261 lines
8.4 KiB
C
/*
|
||
* vim:ts=4:sw=4:expandtab
|
||
*
|
||
* i3 - an improved dynamic tiling window manager
|
||
* © 2009 Michael Stapelberg and contributors (see also: LICENSE)
|
||
*
|
||
* i3-dump-log/main.c: Dumps the i3 SHM log to stdout.
|
||
*
|
||
*/
|
||
#include <config.h>
|
||
|
||
#include "libi3.h"
|
||
#include "shmlog.h"
|
||
|
||
#include <err.h>
|
||
#include <fcntl.h>
|
||
#include <getopt.h>
|
||
#include <i3/ipc.h>
|
||
#include <signal.h>
|
||
#include <stdbool.h>
|
||
#include <stdint.h>
|
||
#include <stdio.h>
|
||
#include <stdlib.h>
|
||
#include <string.h>
|
||
#include <sys/mman.h>
|
||
#include <sys/stat.h>
|
||
#include <unistd.h>
|
||
|
||
#if !defined(__OpenBSD__)
|
||
static uint32_t offset_next_write;
|
||
#endif
|
||
static uint32_t wrap_count;
|
||
|
||
static i3_shmlog_header *header;
|
||
static char *logbuffer,
|
||
*walk;
|
||
static int ipcfd = -1;
|
||
|
||
static volatile bool interrupted = false;
|
||
|
||
static void sighandler(int signal) {
|
||
interrupted = true;
|
||
}
|
||
|
||
static void disable_shmlog(void) {
|
||
const char *disablecmd = "debuglog off; shmlog off";
|
||
if (ipc_send_message(ipcfd, strlen(disablecmd),
|
||
I3_IPC_MESSAGE_TYPE_COMMAND, (uint8_t *)disablecmd) != 0)
|
||
err(EXIT_FAILURE, "IPC send");
|
||
|
||
/* Ensure the command was sent by waiting for the reply: */
|
||
uint32_t reply_length = 0;
|
||
uint8_t *reply = NULL;
|
||
if (ipc_recv_message(ipcfd, I3_IPC_REPLY_TYPE_COMMAND,
|
||
&reply_length, &reply) != 0) {
|
||
err(EXIT_FAILURE, "IPC recv");
|
||
}
|
||
free(reply);
|
||
}
|
||
|
||
static int check_for_wrap(void) {
|
||
if (wrap_count == header->wrap_count)
|
||
return 0;
|
||
|
||
/* The log wrapped. Print the remaining content and reset walk to the top
|
||
* of the log. */
|
||
wrap_count = header->wrap_count;
|
||
const int len = (logbuffer + header->offset_last_wrap) - walk;
|
||
swrite(STDOUT_FILENO, walk, len);
|
||
walk = logbuffer + sizeof(i3_shmlog_header);
|
||
return 1;
|
||
}
|
||
|
||
static void print_till_end(void) {
|
||
check_for_wrap();
|
||
const int len = (logbuffer + header->offset_next_write) - walk;
|
||
swrite(STDOUT_FILENO, walk, len);
|
||
walk += len;
|
||
}
|
||
|
||
void errorlog(char *fmt, ...) {
|
||
va_list args;
|
||
|
||
va_start(args, fmt);
|
||
vfprintf(stderr, fmt, args);
|
||
va_end(args);
|
||
}
|
||
|
||
int main(int argc, char *argv[]) {
|
||
int o, option_index = 0;
|
||
bool verbose = false;
|
||
#if !defined(__OpenBSD__)
|
||
bool follow = false;
|
||
#endif
|
||
|
||
static struct option long_options[] = {
|
||
{"version", no_argument, 0, 'v'},
|
||
{"verbose", no_argument, 0, 'V'},
|
||
#if !defined(__OpenBSD__)
|
||
{"follow", no_argument, 0, 'f'},
|
||
#endif
|
||
{"help", no_argument, 0, 'h'},
|
||
{0, 0, 0, 0}
|
||
};
|
||
|
||
#if !defined(__OpenBSD__)
|
||
char *options_string = "s:vfVh";
|
||
#else
|
||
char *options_string = "vVh";
|
||
#endif
|
||
|
||
while ((o = getopt_long(argc, argv, options_string, long_options, &option_index)) != -1) {
|
||
if (o == 'v') {
|
||
printf("i3-dump-log " I3_VERSION "\n");
|
||
return 0;
|
||
} else if (o == 'V') {
|
||
verbose = true;
|
||
#if !defined(__OpenBSD__)
|
||
} else if (o == 'f') {
|
||
follow = true;
|
||
#endif
|
||
} else if (o == 'h') {
|
||
printf("i3-dump-log " I3_VERSION "\n");
|
||
#if !defined(__OpenBSD__)
|
||
printf("i3-dump-log [-fhVv]\n");
|
||
#else
|
||
printf("i3-dump-log [-hVv]\n");
|
||
#endif
|
||
return 0;
|
||
}
|
||
}
|
||
|
||
char *shmname = root_atom_contents("I3_SHMLOG_PATH", NULL, 0);
|
||
if (shmname == NULL) {
|
||
/* Something failed. Let’s invest a little effort to find out what it
|
||
* is. This is hugely helpful for users who want to debug i3 but are
|
||
* not used to the procedure yet. */
|
||
xcb_connection_t *conn;
|
||
int screen;
|
||
if ((conn = xcb_connect(NULL, &screen)) == NULL ||
|
||
xcb_connection_has_error(conn)) {
|
||
fprintf(stderr, "i3-dump-log: ERROR: Cannot connect to X11.\n\n");
|
||
if (getenv("DISPLAY") == NULL) {
|
||
fprintf(stderr, "Your DISPLAY environment variable is not set.\n");
|
||
fprintf(stderr, "Are you running i3-dump-log via SSH or on a virtual console?\n");
|
||
fprintf(stderr, "Try DISPLAY=:0 i3-dump-log\n");
|
||
exit(1);
|
||
}
|
||
fprintf(stderr, "FYI: The DISPLAY environment variable is set to \"%s\".\n", getenv("DISPLAY"));
|
||
exit(1);
|
||
}
|
||
if (root_atom_contents("I3_CONFIG_PATH", conn, screen) != NULL) {
|
||
fprintf(stderr, "i3-dump-log: i3 is running, but SHM logging is not enabled. Enabling SHM log now while i3-dump-log is running\n\n");
|
||
ipcfd = ipc_connect(NULL);
|
||
const char *enablecmd = "debuglog on; shmlog 5242880";
|
||
if (ipc_send_message(ipcfd, strlen(enablecmd),
|
||
I3_IPC_MESSAGE_TYPE_COMMAND, (uint8_t *)enablecmd) != 0)
|
||
err(EXIT_FAILURE, "IPC send");
|
||
/* By the time we receive a reply, I3_SHMLOG_PATH is set: */
|
||
uint32_t reply_length = 0;
|
||
uint8_t *reply = NULL;
|
||
if (ipc_recv_message(ipcfd, I3_IPC_REPLY_TYPE_COMMAND,
|
||
&reply_length, &reply) != 0) {
|
||
err(EXIT_FAILURE, "IPC recv");
|
||
}
|
||
free(reply);
|
||
|
||
atexit(disable_shmlog);
|
||
|
||
/* Retry: */
|
||
shmname = root_atom_contents("I3_SHMLOG_PATH", NULL, 0);
|
||
if (shmname == NULL && !is_debug_build()) {
|
||
fprintf(stderr, "You seem to be using a release version of i3:\n %s\n\n", I3_VERSION);
|
||
fprintf(stderr, "Release versions do not use SHM logging by default,\ntherefore i3-dump-log does not work.\n\n");
|
||
fprintf(stderr, "Please follow this guide instead:\nhttps://i3wm.org/docs/debugging-release-version.html\n");
|
||
exit(1);
|
||
}
|
||
}
|
||
if (shmname == NULL) {
|
||
errx(EXIT_FAILURE, "Cannot get I3_SHMLOG_PATH atom contents. Is i3 running on this display?");
|
||
}
|
||
}
|
||
|
||
if (*shmname == '\0')
|
||
errx(EXIT_FAILURE, "Cannot dump log: SHM logging is disabled in i3.");
|
||
|
||
struct stat statbuf;
|
||
|
||
/* NB: While we must never write, we need O_RDWR for the pthread condvar. */
|
||
int logbuffer_shm = shm_open(shmname, O_RDWR, 0);
|
||
if (logbuffer_shm == -1)
|
||
err(EXIT_FAILURE, "Could not shm_open SHM segment for the i3 log (%s)", shmname);
|
||
|
||
if (fstat(logbuffer_shm, &statbuf) != 0)
|
||
err(EXIT_FAILURE, "stat(%s)", shmname);
|
||
|
||
/* NB: While we must never write, we need PROT_WRITE for the pthread condvar. */
|
||
logbuffer = mmap(NULL, statbuf.st_size, PROT_READ | PROT_WRITE, MAP_SHARED, logbuffer_shm, 0);
|
||
if (logbuffer == MAP_FAILED)
|
||
err(EXIT_FAILURE, "Could not mmap SHM segment for the i3 log");
|
||
|
||
header = (i3_shmlog_header *)logbuffer;
|
||
|
||
if (verbose)
|
||
printf("next_write = %d, last_wrap = %d, logbuffer_size = %d, shmname = %s\n",
|
||
header->offset_next_write, header->offset_last_wrap, header->size, shmname);
|
||
free(shmname);
|
||
walk = logbuffer + header->offset_next_write;
|
||
|
||
/* We first need to print old content in case there was at least one
|
||
* wrapping already. */
|
||
|
||
if (*walk != '\0') {
|
||
/* In case there was a write to the buffer already, skip the first
|
||
* old line, it very likely is mangled. Not a problem, though, the log
|
||
* is chatty enough to have plenty lines left. */
|
||
while (*walk != '\n')
|
||
walk++;
|
||
walk++;
|
||
}
|
||
|
||
/* In case there was no wrapping, this is a no-op, otherwise it prints the
|
||
* old lines. */
|
||
wrap_count = 0;
|
||
check_for_wrap();
|
||
|
||
/* Then start from the beginning and print the newer lines */
|
||
walk = logbuffer + sizeof(i3_shmlog_header);
|
||
print_till_end();
|
||
|
||
#if !defined(__OpenBSD__)
|
||
if (!follow) {
|
||
return 0;
|
||
}
|
||
|
||
/* Handle SIGINT gracefully to invoke atexit handlers, if any. */
|
||
struct sigaction action;
|
||
action.sa_handler = sighandler;
|
||
sigemptyset(&action.sa_mask);
|
||
action.sa_flags = 0;
|
||
sigaction(SIGINT, &action, NULL);
|
||
|
||
/* Since pthread_cond_wait() expects a mutex, we need to provide one.
|
||
* To not lock i3 (that’s bad, mhkay?) we just define one outside of
|
||
* the shared memory. */
|
||
pthread_mutex_t dummy_mutex = PTHREAD_MUTEX_INITIALIZER;
|
||
pthread_mutex_lock(&dummy_mutex);
|
||
while (!interrupted) {
|
||
pthread_cond_wait(&(header->condvar), &dummy_mutex);
|
||
/* If this was not a spurious wakeup, print the new lines. */
|
||
if (header->offset_next_write != offset_next_write) {
|
||
offset_next_write = header->offset_next_write;
|
||
print_till_end();
|
||
}
|
||
}
|
||
|
||
#endif
|
||
exit(0);
|
||
return 0;
|
||
}
|