Use constants and macros for control chars.

1 files changed, 14 insertions, 8 deletions

diff --git a/pw.c b/pw.c
index 8aa8cf9..f4d7ad1 100644
--- a/pw.c
+++ b/pw.c
@@ -15,6 +15,12 @@
 #include <errno.h>
 #include <regex.h>
 
+#define ctrl(ch) ((ch) & 0x1f)
+#define BS 8
+#define CR 13
+#define ESC 27
+#define DEL 127
+
 enum status_flags {
   stat_dirty = 1,   // display needs refresh
   stat_eof = 2,     // end of data reached
@@ -137,7 +143,7 @@ static char *addch(char *line, int ch)
 
 static char *addchesc(char *line, int ch)
 {
-  if (ch == 127) {
+  if (ch == DEL) {
     line = addch(line, '^');
     line = addch(line, '?');
   } else if (ch < 32) {
@@ -636,11 +642,11 @@ int main(int argc, char **argv)
             if ((stat & stat_eof) == 0)
               stat |= (stat_dirty | stat_susp);
             break;
-          case 13:
+          case CR:
             stat &= ~stat_susp;
             stat |= stat_dirty;
             break;
-          case 27:
+          case ESC:
             kbd_state = kbd_esc;
             break;
           case ':':
@@ -693,9 +699,9 @@ int main(int argc, char **argv)
           // fallthrough
         case kbd_colon:
           switch (ch) {
-          case 27: case 13: case 3:
+          case ESC: case CR: case ctrl('c'):
             stat |= stat_dirty;
-            if (ch == 13) {
+            if (ch == CR) {
               if (kbd_state == kbd_colon && cmdbuf[1]) {
                 execute(cmdbuf, &stat);
                 if (cmdbuf[0] != 0) {
@@ -722,7 +728,7 @@ int main(int argc, char **argv)
             kbd_state = kbd_cmd;
             curcmd = 0;
             break;
-          case 8: case 127:
+          case BS: case DEL:
             {
               size_t len = strlen(cmdbuf);
               if (len == 1) {
@@ -734,10 +740,10 @@ int main(int argc, char **argv)
               }
             }
             break;
-          case 21:
+          case ctrl('u'):
             cmdbuf[1] = 0;
             break;
-          case 23:
+          case ctrl('w'):
             {
               size_t len = strlen(cmdbuf);
               while (len > 1 && isspace((unsigned char) cmdbuf[len - 1]))