+/*
+ * i3bar - an xcb-based status- and ws-bar for i3
+ *
+ * © 2010-2011 Axel Wagner and contributors
+ *
+ * See file LICNSE for license information
+ *
+ * src/child.c: Getting Input for the statusline
+ *
+ */
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
+#include <sys/wait.h>
#include <signal.h>
#include <stdio.h>
#include <fcntl.h>
#include "common.h"
-ev_io *child_io;
+/* Global variables for child_*() */
+pid_t child_pid;
+
+/* stdin- and sigchild-watchers */
+ev_io *stdin_io;
ev_child *child_sig;
+/* The buffer statusline points to */
+char *statusline_buffer = NULL;
+
+/*
+ * Stop and free() the stdin- and sigchild-watchers
+ *
+ */
void cleanup() {
- ev_io_stop(main_loop, child_io);
- ev_child_stop(main_loop, child_sig);
- FREE(child_io);
- FREE(child_sig);
- FREE(statusline);
-}
+ if (stdin_io != NULL) {
+ ev_io_stop(main_loop, stdin_io);
+ FREE(stdin_io);
+ FREE(statusline_buffer);
+ /* statusline pointed to memory within statusline_buffer */
+ statusline = NULL;
+ }
-void strip_dzen_formats(char *buffer) {
- char *src = buffer;
- char *dest = buffer;
- while (*src != '\0') {
- if (*src == '^') {
- if (!strncmp(src, "^ro", strlen("^ro"))) {
- *(dest++) = ' ';
- *(dest++) = '|';
- *(dest++) = ' ';
- }
- while (*src != ')') {
- src++;
- }
- src++;
- } else {
- *dest = *src;
- src++;
- dest++;
- }
+ if (child_sig != NULL) {
+ ev_child_stop(main_loop, child_sig);
+ FREE(child_sig);
}
- *(--dest) = '\0';
}
-void child_io_cb(struct ev_loop *loop, ev_io *watcher, int revents) {
+/*
+ * Callbalk for stdin. We read a line from stdin and store the result
+ * in statusline
+ *
+ */
+void stdin_io_cb(struct ev_loop *loop, ev_io *watcher, int revents) {
int fd = watcher->fd;
int n = 0;
int rec = 0;
int buffer_len = STDIN_CHUNK_SIZE;
char *buffer = malloc(buffer_len);
- memset(buffer, '\0', buffer_len);
+ buffer[0] = '\0';
while(1) {
n = read(fd, buffer + rec, buffer_len - rec);
if (n == -1) {
if (errno == EAGAIN) {
+ /* remove trailing newline and finish up */
+ buffer[rec-1] = '\0';
break;
}
- printf("ERROR: read() failed!");
+ ELOG("read() failed!: %s\n", strerror(errno));
exit(EXIT_FAILURE);
}
if (n == 0) {
- if (rec == buffer_len) {
- char *tmp = buffer;
- buffer = malloc(buffer_len + STDIN_CHUNK_SIZE);
- memset(buffer, '\0', buffer_len);
- strncpy(buffer, tmp, buffer_len);
- buffer_len += STDIN_CHUNK_SIZE;
- FREE(tmp);
- } else {
- break;
+ if (rec != 0) {
+ /* remove trailing newline and finish up */
+ buffer[rec-1] = '\0';
}
+
+ /* end of file, kill the watcher */
+ ELOG("stdin: received EOF\n");
+ cleanup();
+ draw_bars();
+ return;
}
rec += n;
+
+ if (rec == buffer_len) {
+ buffer_len += STDIN_CHUNK_SIZE;
+ buffer = realloc(buffer, buffer_len);
+ }
}
- if (strlen(buffer) == 0) {
+ if (*buffer == '\0') {
FREE(buffer);
return;
}
- strip_dzen_formats(buffer);
- FREE(statusline);
- statusline = buffer;
- printf("%s", buffer);
+ FREE(statusline_buffer);
+ statusline = statusline_buffer = buffer;
+ for (n = 0; buffer[n] != '\0'; ++n) {
+ if (buffer[n] == '\n')
+ statusline = &buffer[n + 1];
+ }
+ DLOG("%s\n", statusline);
draw_bars();
}
+/*
+ * We received a sigchild, meaning, that the child-process terminated.
+ * We simply free the respective data-structures and don't care for input
+ * anymore
+ *
+ */
void child_sig_cb(struct ev_loop *loop, ev_child *watcher, int revents) {
- printf("Child (pid: %d) unexpectedly exited with status %d\n", child_pid, watcher->rstatus);
+ ELOG("Child (pid: %d) unexpectedly exited with status %d\n",
+ child_pid,
+ watcher->rstatus);
cleanup();
}
+/*
+ * Start a child-process with the specified command and reroute stdin.
+ * We actually start a $SHELL to execute the command so we don't have to care
+ * about arguments and such
+ *
+ */
void start_child(char *command) {
- int fd[2];
- pipe(fd);
- child_pid = fork();
- switch (child_pid) {
- case -1:
- printf("ERROR: Couldn't fork()");
- exit(EXIT_FAILURE);
- case 0:
- close(fd[0]);
-
- dup2(fd[1], STDOUT_FILENO);
+ child_pid = 0;
+ if (command != NULL) {
+ int fd[2];
+ pipe(fd);
+ child_pid = fork();
+ switch (child_pid) {
+ case -1:
+ ELOG("Couldn't fork(): %s\n", strerror(errno));
+ exit(EXIT_FAILURE);
+ case 0:
+ /* Child-process. Reroute stdout and start shell */
+ close(fd[0]);
+
+ dup2(fd[1], STDOUT_FILENO);
+
+ static const char *shell = NULL;
+
+ if ((shell = getenv("SHELL")) == NULL)
+ shell = "/bin/sh";
+
+ execl(shell, shell, "-c", command, (char*) NULL);
+ return;
+ default:
+ /* Parent-process. Rerout stdin */
+ close(fd[1]);
+
+ dup2(fd[0], STDIN_FILENO);
+
+ /* If hide-on-modifier is set, we start of by sending the
+ * child a SIGSTOP, because the bars aren't mapped at start */
+ if (config.hide_on_modifier) {
+ stop_child();
+ }
- static const char *shell = NULL;
+ break;
+ }
+ }
- if ((shell = getenv("SHELL")) == NULL)
- shell = "/bin/sh";
+ /* We set O_NONBLOCK because blocking is evil in event-driven software */
+ fcntl(STDIN_FILENO, F_SETFL, O_NONBLOCK);
- execl(shell, shell, "-c", command, (char*) NULL);
- break;
- default:
- close(fd[1]);
+ stdin_io = malloc(sizeof(ev_io));
+ ev_io_init(stdin_io, &stdin_io_cb, STDIN_FILENO, EV_READ);
+ ev_io_start(main_loop, stdin_io);
- dup2(fd[0], STDIN_FILENO);
- fcntl(STDIN_FILENO, F_SETFL, O_NONBLOCK);
+ /* We must cleanup, if the child unexpectedly terminates */
+ child_sig = malloc(sizeof(ev_child));
+ ev_child_init(child_sig, &child_sig_cb, child_pid, 0);
+ ev_child_start(main_loop, child_sig);
- child_io = malloc(sizeof(ev_io));
- ev_io_init(child_io, &child_io_cb, STDIN_FILENO, EV_READ);
- ev_io_start(main_loop, child_io);
+}
- /* We must cleanup, if the child unexpectedly terminates */
- child_sig = malloc(sizeof(ev_io));
- ev_child_init(child_sig, &child_sig_cb, child_pid, 0);
- ev_child_start(main_loop, child_sig);
+/*
+ * kill()s the child-process (if existent) and closes and
+ * free()s the stdin- and sigchild-watchers
+ *
+ */
+void kill_child() {
+ if (child_pid != 0) {
+ kill(child_pid, SIGCONT);
+ kill(child_pid, SIGTERM);
+ int status;
+ waitpid(child_pid, &status, 0);
+ child_pid = 0;
+ cleanup();
+ }
+}
- break;
+/*
+ * Sends a SIGSTOP to the child-process (if existent)
+ *
+ */
+void stop_child() {
+ if (child_pid != 0) {
+ kill(child_pid, SIGSTOP);
}
}
-void kill_child() {
- kill(child_pid, SIGQUIT);
- cleanup();
+/*
+ * Sends a SIGCONT to the child-process (if existent)
+ *
+ */
+void cont_child() {
+ if (child_pid != 0) {
+ kill(child_pid, SIGCONT);
+ }
}
projects / i3 / i3 / blobdiff