Optionally set X root window name

[khatus.git] / x5 / khatus.c

diff --git a/x5/khatus.c b/x5/khatus.c
index faef5b1..3897b87 100644 (file)
--- a/x5/khatus.c
+++ b/x5/khatus.c
@@ -1,8 +1,8 @@
-
 #include <fcntl.h>
 #include <unistd.h>
 #include <sys/select.h>
 #include <sys/stat.h>
+#include <X11/Xlib.h>
 
 #include <assert.h>
 #include <ctype.h>
@@ -19,6 +19,7 @@
 
 char *argv0;
 
+/* TODO: Convert file list to file array. */
 typedef struct File File;
 struct File {
        char   *name;
@@ -37,12 +38,14 @@ struct Config {
        File * files;
        int    file_count;
        int    total_width;
+       int    output_to_x_root_window;
 } defaults = {
        .interval    = 1,
        .separator   = "|",
        .files       = NULL,
        .file_count  = 0,
        .total_width = 0,
+       .output_to_x_root_window = 0,
 };
 
 void
@@ -171,6 +174,11 @@ parse_opts_opt(Config *cfg, int argc, char *argv[], int i)
        switch (argv[i][1]) {
                case 'i': parse_opts_opt_i(cfg, argc, argv, ++i); break;  /* TODO: Generic set_int */
                case 's': parse_opts_opt_s(cfg, argc, argv, ++i); break;  /* TODO: Generic set_str */
+               case 'x': {
+                       cfg->output_to_x_root_window = 1;
+                       opts_parse_any(cfg, argc, argv, ++i);
+                       break;
+               }
                default : usage("Option \"%s\" is invalid\n", argv[i]);
        }
 }
@@ -237,28 +245,21 @@ opts_parse(Config *cfg, int argc, char *argv[], int i)
 void
 read_one(File *f, char *buf)
 {
-       ssize_t n;
+       ssize_t current;
+       ssize_t total;
        char *b;
+       char c;
 
+       current = 0;
+       total = 0;
+       c = '\0';
        b = buf + f->pos;
        memset(b, ' ', f->width);
-       /* TODO: Read upto \n or width */
-       while ((n = read(f->fd, b, f->width)) > 0) {
-               b += n;
-               debug("read %zd from %s\n", n, f->name);
-       }
-
-       if (n > -1) {
-               if (*(b - 1) == '\n')
-                       *(b - 1) = ' ';
-       } else {
-               error(
-                       "Failed to read: \"%s\". Error: %s\n",
-                       f->name,
-                       strerror(errno)
-               );
-       }
-
+       while ((current = read(f->fd, &c, 1)) && c != '\n' && c != '\0' && total++ < f->width)
+               *b++ = c;
+       if (current == -1)
+               error("Failed to read: \"%s\". Error: %s\n", f->name, strerror(errno));
+       /* TODO Record timestamp read */
        close(f->fd);
        f->fd = -1;
 }
@@ -272,7 +273,6 @@ read_all(Config *cfg, char *buf)
        struct stat st;
 
        FD_ZERO(&fds);
-
        /* TODO: Check TTL */
        for (File *f = cfg->files; f; f = f->next) {
                /* TODO: Create the FIFO if it doesn't already exist. */
@@ -313,6 +313,7 @@ main(int argc, char *argv[])
        int prefix = 0;
        char *buf;
        Config *cfg = &defaults;
+       Display *display;
 
        argv0 = argv[0];
 
@@ -345,10 +346,23 @@ main(int argc, char *argv[])
                }
        }
 
-       printf("%s\n", buf);
+       if (cfg->output_to_x_root_window && !(display = XOpenDisplay(NULL)))
+               fatal("XOpenDisplay failed with: %p\n", display);
        /* TODO: nanosleep and nano time diff */
        for (;;) {
+               /* TODO: Check TTL and maybe blank-out */
+               /* TODO: How to trigger TTL check? On select? Alarm signal? */
+               /* TODO: Set timeout on read_all based on diff of last time of
+                *       read_all and desired time of next TTL check.
+                * */
                read_all(cfg, buf);
-               printf("%s\n", buf);
+               if (cfg->output_to_x_root_window) {
+                       if (XStoreName(display, DefaultRootWindow(display), buf) < 0)
+                               fatal("XStoreName failed.\n");
+                       XFlush(display);
+               } else {
+                       puts(buf);
+                       fflush(stdout);
+               }
        }
 }