Cleanup; further optimization of updatestatus and updateblock

GNUmakefile

@@ -8,7 +8,7 @@ X11LIBS := $(shell pkg-config --libs x11)
 
 all: dwmblocks sigdwmblocks xgetrootname
 
-dwmblocks: dwmblocks.c blocks.h
+dwmblocks: dwmblocks.c config.h block.h
 	${CC} -o $@ -Wno-missing-field-initializers -Wno-unused-parameter ${CFLAGS} ${X11CFLAGS} $< ${X11LIBS}
 
 sigdwmblocks: sigdwmblocks.c

README.md

@@ -9,8 +9,8 @@ signaling, clickability, cursor hinting and color.
 
 # Modifying blocks
 
-Blocks are added and removed by editing [blocks.h](blocks.h) file. Read it for
-more info.
+Blocks are added and removed by editing [config.h](config.h) file. Some other
+configurations can also be done through the file. Read it for more info.
 
 > Change the PATH macro defined at the top of the file. It should point to the
 > folder where your scripts are saved.

block.h

@@ -0,0 +1,9 @@
+typedef struct {
+        char *const pathu;
+        char *const pathc;
+        const int interval;
+        const int signal;
+        char curtext[CMDOUTLENGTH + 1 + DELIMITERLENGTH];
+        char prvtext[CMDOUTLENGTH + 1];
+        int len;
+} Block;

config.h

@@ -1,5 +1,12 @@
+/* macro for conveniently specifying pathu and pathc below */
 #define PATH(name)                      "/home/ashish/.local/projects/dwmblocks/blocks/"name
 
+/* buffer size for capturing output of the programs used for updating blocks */
+#define CMDOUTLENGTH                    50
+
+/* buffer size for status text */
+#define STATUSLENGTH                    256
+
 /* DELIMITERENDCHAR must be less than 32.
  * At max, DELIMITERENDCHAR - 1 number of clickable blocks will be allowed.
  * Raw characters larger than DELIMITERENDCHAR and smaller than ' ' in ASCII
@@ -11,6 +18,12 @@
    dwm.c and color codes in your pathu programs. */
 #define DELIMITERENDCHAR                10
 
+/* delimiter specified as an array of characters
+ * don't remove DELIMITERENDCHAR at the end */
+static const char delimiter[] = { ' ', ' ', ' ', DELIMITERENDCHAR };
+
+#include "block.h"
+
 /* If interval of a block is set to 0, the block will only be updated once at
    startup.
  * If interval is set to a negative value, the block will never be updated in
@@ -39,7 +52,3 @@ static Block blocks[] = {
         { PATH("battery.sh"),           PATH("battery_button.sh"),      30,             3},
         { NULL } /* just to mark the end of the array */
 };
-
-/* delimiter specified as an array of characters
- * don't remove DELIMITERENDCHAR at the end */
-static const char delimiter[] = { ' ', ' ', ' ', DELIMITERENDCHAR };

dwmblocks.c

@@ -9,24 +9,12 @@
 #include <unistd.h>
 #include <X11/Xlib.h>
 
-#define CMDOUTLENGTH                    50
-#define STATUSLENGTH                    256
-
 #define NILL                            INT_MIN
 #define LOCKFILE                        "/tmp/dwmblocks.pid"
 
 #define DELIMITERLENGTH                 sizeof delimiter
 
-typedef struct {
-        char *const pathu;
-        char *const pathc;
-        const int interval;
-        const int signal;
-        char curcmdout[CMDOUTLENGTH + 1];
-        char prvcmdout[CMDOUTLENGTH + 1];
-} Block;
-
-#include "blocks.h"
+#include "config.h"
 
 static void buttonhandler(int sig, siginfo_t *info, void *ucontext);
 static void cleanup();
@@ -39,8 +27,8 @@ static void updateblock(Block *block, int sigval);
 static void updatestatus();
 static void writepid();
 
-static int dirty;
 static char statustext[STATUSLENGTH + DELIMITERLENGTH];
+static Block *dirtyblock;
 static Display *dpy;
 static sigset_t blocksigmask;
 
@@ -79,9 +67,9 @@ cleanup()
 void
 setroot()
 {
-        if (dirty) {
+        if (dirtyblock) {
                 updatestatus();
-                dirty = 0;
+                dirtyblock = NULL;
                 XStoreName(dpy, DefaultRootWindow(dpy), statustext);
                 XSync(dpy, False);
         }
@@ -230,17 +218,33 @@ updateblock(Block *block, int sigval)
 
                         close(fd[1]);
                         do
-                                rd = read(fd[0], block->curcmdout + trd, CMDOUTLENGTH - trd);
+                                rd = read(fd[0], block->curtext + trd, CMDOUTLENGTH - trd);
                         while (rd > 0 && (trd += rd) < CMDOUTLENGTH);
                         if (rd == -1) {
                                 perror("updateblock - read");
                                 exit(1);
                         }
                         close(fd[0]);
-                        block->curcmdout[block->curcmdout[trd - 1] == '\n' ? --trd : trd] = '\0';
-                        if (memcmp(block->curcmdout, block->prvcmdout, trd) != 0) {
-                                memcpy(block->prvcmdout, block->curcmdout, trd);
-                                dirty = 1;
+                        if (trd == 0) {
+                                if (block->prvtext[0] != '\0') {
+                                        block->prvtext[0] = '\0';
+                                        if (!dirtyblock || block < dirtyblock)
+                                                dirtyblock = block;
+                                }
+                                block->len = 0;
+                        } else {
+                                if (block->curtext[trd - 1] == '\n')
+                                        trd--;
+                                block->curtext[trd++] = block->signal;
+                                if (memcmp(block->curtext, block->prvtext, trd) != 0) {
+                                        memcpy(block->prvtext, block->curtext, trd);
+                                        if (!dirtyblock || block < dirtyblock)
+                                                dirtyblock = block;
+                                }
+                                if (!block->pathc)
+                                        trd--;
+                                memcpy(block->curtext + trd, delimiter, DELIMITERLENGTH);
+                                block->len = trd + DELIMITERLENGTH;
                         }
                 }
         }
@@ -250,21 +254,17 @@ void
 updatestatus()
 {
         char *s = statustext;
-        size_t len;
 
-        for (Block *block = blocks; block->pathu; block++) {
-                if ((len = strlen(block->curcmdout)) == 0)
-                        continue;
-                memcpy(s, block->curcmdout, len);
-                s += len;
-                if (block->pathc)
-                        *(s++) = block->signal;
-                memcpy(s, delimiter, DELIMITERLENGTH);
-                s += DELIMITERLENGTH;
+        for (Block *block = blocks; block < dirtyblock; block++)
+                s += block->len;
+        for (Block *block = dirtyblock; block->pathu; block++) {
+                memcpy(s, block->curtext, block->len);
+                s += block->len;
         }
         if (s != statustext)
-                s -= DELIMITERLENGTH;
-        *s = '\0';
+                *(s - DELIMITERLENGTH) = '\0';
+        else
+                *s = '\0';
 }
 
 void