Initial commit

1 files changed, 295 insertions, 0 deletions

diff --git a/dwmblocks/dwmblocks.c b/dwmblocks/dwmblocks.c
new file mode 100755
index 0000000..6983418
--- /dev/null
+++ b/dwmblocks/dwmblocks.c
@@ -0,0 +1,295 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <time.h>
+#include <signal.h>
+#include <errno.h>
+#include <X11/Xlib.h>
+#include <sys/signalfd.h>
+#include <poll.h>
+#define LENGTH(X) (sizeof(X) / sizeof (X[0]))
+#define CMDLENGTH		50
+
+typedef struct {
+	char* icon;
+	char* command;
+	unsigned int interval;
+	unsigned int signal;
+} Block;
+void sighandler();
+void buttonhandler(int ssi_int);
+void replace(char *str, char old, char new);
+void remove_all(char *str, char to_remove);
+void getcmds(int time);
+void getsigcmds(int signal);
+void setupsignals();
+int getstatus(char *str, char *last);
+void setroot();
+void statusloop();
+void termhandler(int signum);
+
+
+#include "config.h"
+
+static Display *dpy;
+static int screen;
+static Window root;
+static char statusbar[LENGTH(blocks)][CMDLENGTH] = {0};
+static char statusstr[2][256];
+static int statusContinue = 1;
+static int signalFD;
+static int timerInterval = -1;
+static void (*writestatus) () = setroot;
+
+void replace(char *str, char old, char new)
+{
+	for(char * c = str; *c; c++)
+		if(*c == old)
+			*c = new;
+}
+
+// the previous function looked nice but unfortunately it didnt work if to_remove was in any position other than the last character
+// theres probably still a better way of doing this
+void remove_all(char *str, char to_remove) {
+	char *read = str;
+	char *write = str;
+	while (*read) {
+		if (*read != to_remove) {
+			*write++ = *read;
+		}
+		++read;
+	}
+	*write = '\0';
+}
+
+int gcd(int a, int b)
+{
+	int temp;
+	while (b > 0){
+		temp = a % b;
+
+		a = b;
+		b = temp;
+	}
+	return a;
+}
+
+
+//opens process *cmd and stores output in *output
+void getcmd(const Block *block, char *output)
+{
+	if (block->signal)
+	{
+		output[0] = block->signal;
+		output++;
+	}
+	char *cmd = block->command;
+	FILE *cmdf = popen(cmd,"r");
+	if (!cmdf){
+        //printf("failed to run: %s, %d\n", block->command, errno);
+		return;
+    }
+    char tmpstr[CMDLENGTH] = "";
+    // TODO decide whether its better to use the last value till next time or just keep trying while the error was the interrupt
+    // this keeps trying to read if it got nothing and the error was an interrupt
+    //  could also just read to a separate buffer and not move the data over if interrupted
+    //  this way will take longer trying to complete 1 thing but will get it done
+    //  the other way will move on to keep going with everything and the part that failed to read will be wrong till its updated again
+    // either way you have to save the data to a temp buffer because when it fails it writes nothing and then then it gets displayed before this finishes
+	char * s;
+    int e;
+    do {
+        errno = 0;
+        s = fgets(tmpstr, CMDLENGTH-(strlen(delim)+1), cmdf);
+        e = errno;
+    } while (!s && e == EINTR);
+	pclose(cmdf);
+	int i = strlen(block->icon);
+	strcpy(output, block->icon);
+    strcpy(output+i, tmpstr);
+	remove_all(output, '\n');
+	i = strlen(output);
+    if ((i > 0 && block != &blocks[LENGTH(blocks) - 1])){
+        strcat(output, delim);
+    }
+    i+=strlen(delim);
+	output[i++] = '\0';
+}
+
+void getcmds(int time)
+{
+	const Block* current;
+	for(int i = 0; i < LENGTH(blocks); i++)
+	{
+		current = blocks + i;
+		if ((current->interval != 0 && time % current->interval == 0) || time == -1){
+			getcmd(current,statusbar[i]);
+        }
+	}
+}
+
+void getsigcmds(int signal)
+{
+	const Block *current;
+	for (int i = 0; i < LENGTH(blocks); i++)
+	{
+		current = blocks + i;
+		if (current->signal == signal){
+			getcmd(current,statusbar[i]);
+        }
+	}
+}
+
+void setupsignals()
+{
+	sigset_t signals;
+	sigemptyset(&signals);
+	sigaddset(&signals, SIGALRM); // Timer events
+	sigaddset(&signals, SIGUSR1); // Button events
+	// All signals assigned to blocks
+	for (size_t i = 0; i < LENGTH(blocks); i++)
+		if (blocks[i].signal > 0)
+			sigaddset(&signals, SIGRTMIN + blocks[i].signal);
+	// Create signal file descriptor for pooling
+	signalFD = signalfd(-1, &signals, 0);
+	// Block all real-time signals
+	for (int i = SIGRTMIN; i <= SIGRTMAX; i++) sigaddset(&signals, i);
+	sigprocmask(SIG_BLOCK, &signals, NULL);
+	// Do not transform children into zombies
+	struct sigaction sigchld_action = {
+  		.sa_handler = SIG_DFL,
+  		.sa_flags = SA_NOCLDWAIT
+	};
+	sigaction(SIGCHLD, &sigchld_action, NULL);
+
+}
+
+int getstatus(char *str, char *last)
+{
+	strcpy(last, str);
+	str[0] = '\0';
+    for(int i = 0; i < LENGTH(blocks); i++) {
+		strcat(str, statusbar[i]);
+        if (i == LENGTH(blocks) - 1)
+            strcat(str, " ");
+    }
+	str[strlen(str)-1] = '\0';
+	return strcmp(str, last);//0 if they are the same
+}
+
+void setroot()
+{
+	if (!getstatus(statusstr[0], statusstr[1]))//Only set root if text has changed.
+		return;
+	Display *d = XOpenDisplay(NULL);
+	if (d) {
+		dpy = d;
+	}
+	screen = DefaultScreen(dpy);
+	root = RootWindow(dpy, screen);
+	XStoreName(dpy, root, statusstr[0]);
+	XCloseDisplay(dpy);
+}
+
+void pstdout()
+{
+	if (!getstatus(statusstr[0], statusstr[1]))//Only write out if text has changed.
+		return;
+	printf("%s\n",statusstr[0]);
+	fflush(stdout);
+}
+
+
+void statusloop()
+{
+	setupsignals();
+    // first figure out the default wait interval by finding the
+    // greatest common denominator of the intervals
+    for(int i = 0; i < LENGTH(blocks); i++){
+        if(blocks[i].interval){
+            timerInterval = gcd(blocks[i].interval, timerInterval);
+        }
+    }
+    getcmds(-1);     // Fist time run all commands
+    raise(SIGALRM);  // Schedule first timer event
+    int ret;
+    struct pollfd pfd[] = {{.fd = signalFD, .events = POLLIN}};
+    while (statusContinue) {
+        // Wait for new signal
+        ret = poll(pfd, sizeof(pfd) / sizeof(pfd[0]), -1);
+        if (ret < 0 || !(pfd[0].revents & POLLIN)) break;
+        sighandler(); // Handle signal
+    }
+}
+
+void sighandler()
+{
+	static int time = 0;
+	struct signalfd_siginfo si;
+	int ret = read(signalFD, &si, sizeof(si));
+	if (ret < 0) return;
+	int signal = si.ssi_signo;
+	switch (signal) {
+		case SIGALRM:
+			// Execute blocks and schedule the next timer event
+			getcmds(time);
+			alarm(timerInterval);
+			time += timerInterval;
+			break;
+		case SIGUSR1:
+			// Handle buttons
+			buttonhandler(si.ssi_int);
+			return;
+		default:
+			// Execute the block that has the given signal
+			getsigcmds(signal - SIGRTMIN);
+			break;
+	}
+	writestatus();
+}
+
+void buttonhandler(int ssi_int)
+{
+	char button[2] = {'0' + ssi_int & 0xff, '\0'};
+	pid_t process_id = getpid();
+	int sig = ssi_int >> 8;
+	if (fork() == 0)
+	{
+		const Block *current;
+		for (int i = 0; i < LENGTH(blocks); i++)
+		{
+			current = blocks + i;
+			if (current->signal == sig)
+				break;
+		}
+		char shcmd[1024];
+		sprintf(shcmd,"%s && kill -%d %d",current->command, current->signal+34,process_id);
+		char *command[] = { "/bin/sh", "-c", shcmd, NULL };
+		setenv("BLOCK_BUTTON", button, 1);
+		setsid();
+		execvp(command[0], command);
+		exit(EXIT_SUCCESS);
+	}
+}
+
+
+void termhandler(int signum)
+{
+	statusContinue = 0;
+}
+
+int main(int argc, char** argv)
+{
+	for(int i = 0; i < argc; i++)
+	{
+		if (!strcmp("-d",argv[i]))
+			delim = argv[++i];
+		else if(!strcmp("-p",argv[i]))
+			writestatus = pstdout;
+	}
+	signal(SIGTERM, termhandler);
+	signal(SIGINT, termhandler);
+	statusloop();
+	close(signalFD);
+}