Change execute function's interface.

1 files changed, 57 insertions, 40 deletions

diff --git a/pw.c b/pw.c
index 260a07d..f270587 100644
--- a/pw.c
+++ b/pw.c
@@ -82,6 +82,10 @@ enum status_flags {
   stat_oneshot =  0x0800, // running in the background
 };
 
+typedef enum execode {
+  exec_ok, exec_msg, exec_failed
+} execode;
+
 typedef struct pwstate {
   char **circbuf;
   int nlines;
@@ -205,7 +209,7 @@ static char *dsensure(char *str)
   return dsgrow(0, 0);
 }
 
-static char *dsdup(char *str)
+static char *dsdup(const char *str)
 {
   size_t len = strlen(str);
   char *copy = dsgrow(0, len);
@@ -650,63 +654,64 @@ static int getms(const char *str, char **err)
   return msec;
 }
 
-static void execute(pwstate *pw, char *cmd)
+static execode execute(pwstate *pw, const char *cmd, char *resbuf, size_t size)
 {
-  char *arg = cmd + 2 + strspn(cmd + 2, " \t");
+  execode res = exec_failed;
+  const char *arg = cmd + 2 + strspn(cmd + 2, " \t");
 
   clrline(0);
-  cmd[0] = 0;
 
   switch (cmd[1]) {
   case 'w': case 'a':
     if (arg[0] == 0) {
-      sprintf(cmd, "file name required!");
+      snprintf(resbuf, size, "file name required!");
       break;
     } else {
       FILE *f = fopen(arg, cmd[1] == 'w' ? "w" : "a");
-      int ok = 1;
 
       if (!f) {
-        sprintf(cmd, "unable to open file");
+        snprintf(resbuf, size, "unable to open file");
         break;
       }
 
-      for (int i = 0; ok && i < snaplines[pw->hist]; i++)
+      res = exec_msg;
+
+      for (int i = 0; res == exec_msg && i < snaplines[pw->hist]; i++)
         if (fprintf(f, "%s\n", snapshot[pw->hist][i]) < 0) {
-          sprintf(cmd, "write error!");
-          ok = 0;
+          snprintf(resbuf, size, "write error!");
+          res = exec_failed;
           break;
         }
 
       fclose(f);
-      if (ok)
-        sprintf(cmd, "saved!");
+      if (res == exec_msg)
+        snprintf(resbuf, size, "saved!");
     }
     break;
   case '!':
     if (arg[0] == 0) {
-      sprintf(cmd, "command required!");
+      snprintf(resbuf, size, "command required!");
       break;
     } else {
       FILE *p = popen(arg, "w");
-      int ok = 1;
 
       if (!p) {
-        sprintf(cmd, "unable to open command");
-        fflush(stdout);
+        snprintf(resbuf, size, "unable to open command");
         break;
       }
 
-      for (int i = 0; i < snaplines[pw->hist] && ok; i++)
+      res = exec_msg;
+
+      for (int i = 0; i < snaplines[pw->hist] && res == exec_msg; i++)
         if (fprintf(p, "%s\n", snapshot[pw->hist][i]) < 0) {
-          sprintf(cmd, "write error!");
-          ok = 0;
+          snprintf(resbuf, size, "write error!");
+          res = exec_failed;
           break;
         }
 
       pclose(p);
-      if (ok)
-        sprintf(cmd, "piped!");
+      if (res == exec_msg)
+        snprintf(resbuf, size, "piped!");
     }
     break;
   case 'g':
@@ -715,23 +720,25 @@ static void execute(pwstate *pw, char *cmd)
       grep *gr = &grepstack[ngrep];
 
       if (arg[0] == 0) {
-        sprintf(cmd, "pattern required!");
+        snprintf(resbuf, size, "pattern required!");
         break;
       }
 
       if (ngrep >= maxgrep) {
-        sprintf(cmd, "too many greps");
+        snprintf(resbuf, size, "too many greps");
         break;
       }
 
       if ((grinit(gr, dsdup(arg), cmd[1] == 'v', dsdrop)) != 0) {
-        grerrstr(gr, cmd, cmdsize);
+        grerrstr(gr, resbuf, size);
         grclean(gr);
         break;
       }
 
       if (ngrep++ == 0)
         pw->stat |= stat_grep;
+
+      res = exec_ok;
     }
     break;
   case 'r':
@@ -744,27 +751,34 @@ static void execute(pwstate *pw, char *cmd)
     }
     if (ngrep == 0)
       pw->stat &= ~stat_grep;
+    res = exec_ok;
     break;
   case 'i': case 'l':
     {
       char *err = 0;
       int interval = getms(arg, &err);
 
-      if (interval < 0)
-        snprintf(cmd, cmdsize, "%s", err);
-      else if (cmd[1] == 'i')
+      if (interval < 0) {
+        snprintf(resbuf, size, "%s", err);
+        break;
+      }
+
+      if (cmd[1] == 'i')
         poll_interval = interval;
       else
         long_interval = interval;
 
       dsdrop(err);
+      res = exec_ok;
     }
     break;
   case 'E':
     regex_flags = REG_EXTENDED;
+    res = exec_ok;
     break;
   case 'B':
     regex_flags = 0;
+    res = exec_ok;
     break;
   case 'c':
     if (arg[0] == 0) {
@@ -772,34 +786,38 @@ static void execute(pwstate *pw, char *cmd)
     } else  {
       char *err = 0;
       int val = getznn(arg, &err);
-      if (val < 0)
-        snprintf(cmd, cmdsize, "bad trigger count: %s", err);
-      else
-        sncount = val;
+      if (val < 0) {
+        snprintf(resbuf, size, "bad trigger count: %s", err);
+        break;
+      }
+      sncount = val;
       dsdrop(err);
+      res = exec_ok;
     }
     break;
   case 'f':
     if (arg[0] == 0) {
-      sprintf(cmd, "frequency argument required!");
+      snprintf(resbuf, size, "frequency argument required!");
       break;
     }
     {
       char *err = 0;
       int val = getznn(arg, &err);
-      if (val < 0)
-        snprintf(cmd, cmdsize, "bad trigger freq: %s", err);
-      else
-        tfreq = val;
+      if (val < 0) {
+        snprintf(resbuf, size, "bad trigger freq: %s", err);
+        break;
+      }
+      tfreq = val;
       dsdrop(err);
+      res = exec_ok;
     }
     break;
   default:
-    sprintf(cmd, "bad command");
+    snprintf(resbuf, size, "bad command");
     break;
   }
 
-  fflush(stdout);
+  return res;
 }
 
 static void ttyset(int fd, struct termios *tty)
@@ -1560,8 +1578,7 @@ int main(int argc, char **argv)
               }
 
               if (kbd_state == kbd_colon && pw.cmdbuf[1]) {
-                execute(&pw, pw.cmdbuf);
-                if (pw.cmdbuf[0] != 0) {
+                if (execute(&pw, pw.cmdbuf, pw.cmdbuf, cmdsize) != exec_ok) {
                   kbd_state = kbd_result;
                   break;
                 }