swayfx/swaybar/status_line.c
sghctoma 315b2bf100 Replace getdelim to make swaybar work on FreeBSD
This commit fixes a segfault in swaybar on FreeBSD that was caused by
using getdelim with EOF as delimiter on an infinite stream. The FreeBSD
implementation handles the "no more data, delimiter not found, and EOF
not reached" scenario as an error, so it can't be used to read the
output of status command. This commit replaces the getline/getdelim
calls with reading all available data from the stream in one go.
2018-09-26 20:38:16 +02:00

173 lines
4.8 KiB
C

#define _POSIX_C_SOURCE 200809L
#include <fcntl.h>
#include <sys/ioctl.h>
#include <json-c/json.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <wlr/util/log.h>
#include "swaybar/config.h"
#include "swaybar/event_loop.h"
#include "swaybar/status_line.h"
#include "readline.h"
static void status_line_close_fds(struct status_line *status) {
if (status->read_fd != -1) {
remove_event(status->read_fd);
close(status->read_fd);
status->read_fd = -1;
}
if (status->write_fd != -1) {
close(status->write_fd);
status->write_fd = -1;
}
}
void status_error(struct status_line *status, const char *text) {
status_line_close_fds(status);
status->protocol = PROTOCOL_ERROR;
status->text = text;
}
bool status_handle_readable(struct status_line *status) {
ssize_t read_bytes = 1;
switch (status->protocol) {
case PROTOCOL_UNDEF:
errno = 0;
int available_bytes;
if (ioctl(status->read_fd, FIONREAD, &available_bytes) == -1) {
wlr_log(WLR_ERROR, "Unable to read status command output size");
status_error(status, "[error reading from status command]");
return true;
}
if ((size_t)available_bytes + 1 > status->buffer_size) {
// need room for leading '\0' too
status->buffer_size = available_bytes + 1;
status->buffer = realloc(status->buffer, status->buffer_size);
}
if (status->buffer == NULL) {
wlr_log_errno(WLR_ERROR, "Unable to read status line");
status_error(status, "[error reading from status command]");
return true;
}
read_bytes = read(status->read_fd, status->buffer, available_bytes);
if (read_bytes != available_bytes) {
status_error(status, "[error reading from status command]");
return true;
}
status->buffer[available_bytes] = 0;
// the header must be sent completely the first time round
char *newline = strchr(status->buffer, '\n');
json_object *header, *version;
if (newline != NULL
&& (header = json_tokener_parse(status->buffer))
&& json_object_object_get_ex(header, "version", &version)
&& json_object_get_int(version) == 1) {
wlr_log(WLR_DEBUG, "Using i3bar protocol.");
status->protocol = PROTOCOL_I3BAR;
json_object *click_events;
if (json_object_object_get_ex(header, "click_events", &click_events)
&& json_object_get_boolean(click_events)) {
wlr_log(WLR_DEBUG, "Enabling click events.");
status->click_events = true;
if (write(status->write_fd, "[\n", 2) != 2) {
status_error(status, "[failed to write to status command]");
json_object_put(header);
return true;
}
}
json_object_put(header);
wl_list_init(&status->blocks);
status->tokener = json_tokener_new();
status->buffer_index = strlen(newline + 1);
memmove(status->buffer, newline + 1, status->buffer_index + 1);
return i3bar_handle_readable(status);
}
wlr_log(WLR_DEBUG, "Using text protocol.");
status->protocol = PROTOCOL_TEXT;
status->text = status->buffer;
// intentional fall-through
case PROTOCOL_TEXT:
errno = 0;
while (true) {
if (status->buffer[read_bytes - 1] == '\n') {
status->buffer[read_bytes - 1] = '\0';
}
read_bytes = getline(&status->buffer,
&status->buffer_size, status->read);
if (errno == EAGAIN) {
clearerr(status->read);
return true;
} else if (errno) {
status_error(status, "[error reading from status command]");
return true;
}
}
case PROTOCOL_I3BAR:
return i3bar_handle_readable(status);
default:
return false;
}
}
struct status_line *status_line_init(char *cmd) {
struct status_line *status = calloc(1, sizeof(struct status_line));
status->buffer_size = 8192;
status->buffer = malloc(status->buffer_size);
int pipe_read_fd[2];
int pipe_write_fd[2];
if (pipe(pipe_read_fd) != 0 || pipe(pipe_write_fd) != 0) {
wlr_log(WLR_ERROR, "Unable to create pipes for status_command fork");
exit(1);
}
status->pid = fork();
if (status->pid == 0) {
dup2(pipe_read_fd[1], STDOUT_FILENO);
close(pipe_read_fd[0]);
close(pipe_read_fd[1]);
dup2(pipe_write_fd[0], STDIN_FILENO);
close(pipe_write_fd[0]);
close(pipe_write_fd[1]);
char *const _cmd[] = { "sh", "-c", cmd, NULL, };
execvp(_cmd[0], _cmd);
exit(1);
}
close(pipe_read_fd[1]);
status->read_fd = pipe_read_fd[0];
fcntl(status->read_fd, F_SETFL, O_NONBLOCK);
close(pipe_write_fd[0]);
status->write_fd = pipe_write_fd[1];
fcntl(status->write_fd, F_SETFL, O_NONBLOCK);
status->read = fdopen(status->read_fd, "r");
status->write = fdopen(status->write_fd, "w");
return status;
}
void status_line_free(struct status_line *status) {
status_line_close_fds(status);
kill(status->pid, SIGTERM);
if (status->protocol == PROTOCOL_I3BAR) {
struct i3bar_block *block, *tmp;
wl_list_for_each_safe(block, tmp, &status->blocks, link) {
wl_list_remove(&block->link);
i3bar_block_unref(block);
}
json_tokener_free(status->tokener);
}
free(status->buffer);
free(status);
}