1 files changed, 35 insertions, 10 deletions

diff --git a/pw.c b/pw.c
index 5e52a6c..1abe3d0 100644
--- a/pw.c
+++ b/pw.c
@@ -47,6 +47,7 @@
 
 #define ctrl(ch) ((ch) & 0x1f)
 #define BS 8
+#define TAB 9
 #define CR 13
 #define ESC 27
 #define DEL 127
@@ -94,6 +95,7 @@ typedef struct pwstate {
   int vsplit1, vsplit2, vs2pos;
   int hist;
   int columns;
+  int tstop;
   unsigned stat;
   int sncount, tcount;
   char *curcmd, *savedcmd;
@@ -256,16 +258,25 @@ static char *addch(char *line, int ch)
   abort();
 }
 
-static char *addchesc(char *line, int ch)
+static char *addchesc(char *line, int tstop, int ch)
 {
-  if (ch == DEL) {
+  switch (ch) {
+  case DEL:
     line = addch(line, '^');
     line = addch(line, '?');
-  } else if (ch < 32) {
-    line = addch(line, '^');
-    line = addch(line, ch + 64);
-  } else {
+    break;
+  case TAB:
+    for (size_t len = dslen(line); line = addch(line, ' '), ++len % tstop != 0;)
+      /* empty */;
+    break;
+  default:
+    if (ch < 32) {
+      line = addch(line, '^');
+      line = addch(line, ch + 64);
+      break;
+    }
     line = addch(line, ch);
+    break;
   }
 
   return line;
@@ -682,6 +693,7 @@ static int decodeparms(pwstate *pw, char *parms,
   char *rpane = strtok(0, ", \t");
   char *vs2pos = strtok(0, ", \t");
   char *flags = strtok(0, ", \t");
+  char *tstop = strtok(0, ", \t");
 
   pw->hpos = pw->vsplit1 = pw->vsplit2 = pw->vs2pos = 0;
   pw->stat &= ~stat_save;
@@ -715,6 +727,13 @@ static int decodeparms(pwstate *pw, char *parms,
     pw->stat |= (stat & stat_save);
   }
 
+  if (tstop && ((pw->tstop = getznn(tstop, &err)) < 0 || pw->tstop > 16)) {
+    snprintf(resbuf, size, "bad tab stop size%s: %s\n", tstop, err);
+    if (pw->tstop == 0)
+      pw->tstop = 8;
+    return 0;
+  }
+
   return 1;
 }
 
@@ -898,8 +917,8 @@ static execode execute(pwstate *pw, char *cmd, char *resbuf,
         break;
       }
 
-      fprintf(f, ":p%d,%d,%d,%d,%d\n", pw->hpos, pw->vsplit1, pw->vsplit2,
-              pw->vs2pos, (int) pw->stat & stat_save);
+      fprintf(f, ":p%d,%d,%d,%d,%d,%d\n", pw->hpos, pw->vsplit1, pw->vsplit2,
+              pw->vs2pos, (int) pw->stat & stat_save, pw->tstop);
 
       if (pw->tcount)
         fprintf(f, ":f%d\n", pw->tcount);
@@ -1086,7 +1105,7 @@ void clipsplits(pwstate *pw)
 
 int main(int argc, char **argv)
 {
-  struct pwstate pw = { .columns = 80, .maxlines = 15 };
+  struct pwstate pw = { .columns = 80, .maxlines = 15, .tstop = 8 };
   char *line = 0;
   FILE *tty = fopen("/dev/tty", "r+");
   int maxed = 0;
@@ -1321,7 +1340,7 @@ int main(int argc, char **argv)
     if ((pw.stat & stat_eof) == 0) {
       int ch;
       while ((ch = getc(stdin)) != EOF && ch != '\n' && dslen(line) < maxlen)
-        line = addchesc(line, ch);
+        line = addchesc(line, pw.tstop, ch);
       if (ch == EOF) {
         if (feof(stdin) || (errno != EAGAIN && errno != EWOULDBLOCK)) {
           nfds = 1;
@@ -1617,6 +1636,12 @@ int main(int argc, char **argv)
             if ((pw.stat & stat_eof) == 0)
               pw.stat |= stat_susp;
             break;
+          case 't':
+            if (cmdcount < 1 || cmdcount > 16)
+              cmdcount = 8;
+            pw.tstop = cmdcount;
+            pw.stat |= stat_force;
+            break;
           case CR:
             pw.stat &= ~stat_susp;
             break;