Improve ^C handling:

- ^C didn't work for int21/ah=3f. Corrected -- Do_DosIdle_loop still needs
  to wait even if it doesn't call the idle int
- ^C needs to be echoed to STDOUT for low character functions (ah<0xd) but
  to the device that is read from for handle functions. So we need to pass
  either the STDOUT sft or that device on to the ^C echoer.
- The ^C echo really should print ^C\r\n.
- misc cleanups in break.c.


git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@883 6ac86273-5f31-0410-b378-82cca8765d1b

kernel/break.c

@@ -31,49 +31,48 @@
 #include "globals.h"
 #include "proto.h"
 
-extern void ASMCFUNC spawn_int23(void);
-
 #ifdef VERSION_STRINGS
 static BYTE *RcsId =
     "$Id$";
 #endif
 
-#define CB_FLG *(UBYTE FAR*)MK_FP(0x40, 0x71)
+#define CB_FLG *(UBYTE FAR*)MK_FP(0x0, 0x471)
 #define CB_MSK 0x80
 
-/* Check for ^Break.
+/* Check for ^Break/^C.
-
+ * Three sources are available:
- * Two sources are available:
+ *       1) flag at 40:71 bit 7
- *                                                                              1) flag at 40:71 bit 7
+ *       2) CON stream (if STDIN is redirected somewhere else)
- *                                                                              2) STDIN stream via con_break()
+ *       3) input stream (most likely STDIN)
- */
-int check_handle_break(void)
-{
-  if (CB_FLG & CB_MSK) {
-    CB_FLG &= ~CB_MSK;            /* reset the ^Break flag */
-    handle_break(&syscon);
-  }
-  /* con_break will call handle_break() for CTL_C */
-  return con_break();
-}
-
-/*
- * Handles a ^Break state
- *
  * Actions:
- *                                                                              1) clear the ^Break flag
+ *       1) echo ^C
- *                                                                              2) clear the STDIN stream
+ *       2) clear the STDIN stream
- *                                                                              3) decrease the InDOS flag as the kernel drops back to user space
+ *       3) decrease the InDOS flag as the kernel drops back to user space
- *                                                                              4) invoke INT-23 and never come back
+ *       4) invoke INT-23 and never come back
  */
-void handle_break(struct dhdr FAR **pdev)
+unsigned char check_handle_break(struct dhdr FAR **pdev, int sft_out)
 {
-  echo_char(CTL_C, get_sft_idx(STDOUT));
+  unsigned char c = CTL_C;
-  con_flush(pdev);
+  if (CB_FLG & CB_MSK)
-  if (!ErrorMode)               /* within int21_handler, InDOS is not incremented */
+    CB_FLG &= ~CB_MSK;            /* reset the ^Break flag */
-    if (InDOS)
+  else
-      --InDOS;                  /* fail-safe */
+    c = (unsigned char)ndread(&syscon);
+  if (c == CTL_C)
+  {
+    sft_out = -1;
+    pdev = &syscon;
+  }
+  else if (*pdev != syscon)
+    c = (unsigned char)ndread(pdev);
+  if (c == CTL_C)
+  {
+    con_flush(pdev);
+    echo_ctl_c(pdev, sft_out);
+    if (!ErrorMode)      /* within int21_handler, InDOS is not incremented */
+      if (InDOS)
+        --InDOS;         /* fail-safe */
 
-  spawn_int23();                /* invoke user INT-23 and never come back */
+    spawn_int23();       /* invoke user INT-23 and never come back */
+  }
+  return c;
 }
-

kernel/chario.c

@@ -128,15 +128,15 @@ int StdinBusy(void)
 
 STATIC void Do_DosIdle_loop(struct dhdr FAR **pdev)
 {
-  /* the idle loop is only safe if we're using the character stack */
+  /* the idle int is only safe if we're using the character stack */
-  if (user_r->AH < 0xd)
+  while (Busy(pdev) && (*pdev == syscon || Busy(&syscon)))
-    while (Busy(pdev) && Busy(&syscon))
+    if (user_r->AH < 0xd)
       DosIdle_int();
 }
 
 /* get character from the console - this is how DOS gets
    CTL_C/CTL_S/CTL_P when outputting */
-STATIC int ndread(struct dhdr FAR **pdev)
+int ndread(struct dhdr FAR **pdev)
 {
   CharCmd(pdev, C_NDREAD);
   if (CharReqHdr.r_status & S_BUSY)
@@ -144,35 +144,19 @@ STATIC int ndread(struct dhdr FAR **pdev)
   return CharReqHdr.r_ndbyte;
 }
 
-STATIC void con_skip_char(struct dhdr FAR **pdev)
+STATIC void con_hold(struct dhdr FAR **pdev, int sft_out)
 {
-  if (CharIO(pdev, 0, C_INPUT) == CTL_C)
+  unsigned char c = check_handle_break(pdev, sft_out);
-    handle_break(pdev);
+  if (c == CTL_S)
-}
-
-STATIC void con_hold(struct dhdr FAR **pdev)
-{
-  int c = check_handle_break();
-  if (*pdev != syscon)
-    c = ndread(pdev);
-  if (c == CTL_S || c == CTL_C)
   {
-    con_skip_char(pdev);
+    CharIO(pdev, 0, C_INPUT);
     Do_DosIdle_loop(pdev);
-    /* just wait */
+    /* just wait and then skip a character */
-    check_handle_break();
+    check_handle_break(pdev, sft_out);
-    con_skip_char(pdev);
+    CharIO(pdev, 0, C_INPUT);
   }
 }
 
-int con_break(void)
-{
-  int c = ndread(&syscon);
-  if (c == CTL_C)
-    con_skip_char(&syscon);
-  return c;
-}
-
 /* OUTPUT FUNCTIONS */
 
 #ifdef __WATCOMC__
@@ -231,7 +215,7 @@ STATIC int cooked_write_char(struct dhdr FAR **pdev,
        otherwise check every 32 characters */
     if (*fast_counter <= 0x80)
       /* Test for hold char and ctl_c */
-      con_hold(pdev);
+      con_hold(pdev, -1);
     *fast_counter += 1;
     *fast_counter &= 0x9f;
 
@@ -306,7 +290,7 @@ void write_char_stdout(int c)
 #define iscntrl(c) ((unsigned char)(c) < ' ')
 
 /* this is for handling things like ^C, mostly used in echoed input */
-int echo_char(int c, int sft_idx)
+STATIC int echo_char(int c, int sft_idx)
 {
   int out = c;
   if (iscntrl(c) && c != HT && c != LF && c != CR)
@@ -318,6 +302,16 @@ int echo_char(int c, int sft_idx)
   return c;
 }
 
+void echo_ctl_c(struct dhdr FAR **pdev, int sft_idx)
+{
+  char *buf = "^C\r\n";
+
+  if (sft_idx == -1)
+    cooked_write(pdev, 4, buf);
+  else
+    DosRWSft(sft_idx, 4, buf, XFR_FORCE_WRITE);
+}
+
 STATIC void destr_bs(int sft_idx)
 {
   write_char(BS, sft_idx);
@@ -327,12 +321,12 @@ STATIC void destr_bs(int sft_idx)
 
 /* READ FUNCTIONS */
 
-STATIC int raw_get_char(struct dhdr FAR **pdev, BOOL check_break)
+STATIC int raw_get_char(struct dhdr FAR **pdev, int sft_out, BOOL check_break)
 {
   Do_DosIdle_loop(pdev);
   if (check_break)
   {
-    con_hold(pdev);
+    con_hold(pdev, sft_out);
     Do_DosIdle_loop(pdev);
   }
   return CharIO(pdev, 0, C_INPUT);
@@ -344,7 +338,7 @@ long cooked_read(struct dhdr FAR **pdev, size_t n, char FAR *bp)
   int c;
   while(n--)
   {
-    c = raw_get_char(pdev, TRUE);
+    c = raw_get_char(pdev, -1, TRUE);
     if (c < 0)
       return c;
     if (c == 256)
@@ -357,26 +351,26 @@ long cooked_read(struct dhdr FAR **pdev, size_t n, char FAR *bp)
   return xfer;
 }
 
-unsigned char read_char(int sft_idx, BOOL check_break)
+unsigned char read_char(int sft_in, int sft_out, BOOL check_break)
 {
   unsigned char c;
-  struct dhdr FAR *dev = sft_to_dev(idx_to_sft(sft_idx));
+  struct dhdr FAR *dev = sft_to_dev(idx_to_sft(sft_in));
 
   if (dev)
-    return (unsigned char)raw_get_char(&dev, check_break);
+    return (unsigned char)raw_get_char(&dev, sft_out, check_break);
 
-  DosRWSft(sft_idx, 1, &c, XFR_READ);
+  DosRWSft(sft_in, 1, &c, XFR_READ);
   return c;
 }
 
-STATIC unsigned char read_char_check_break(int sft_idx)
+STATIC unsigned char read_char_check_break(int sft_in, int sft_out)
 {
-  return read_char(sft_idx, TRUE);
+  return read_char(sft_in, sft_out, TRUE);
 }
 
 unsigned char read_char_stdin(BOOL check_break)
 {
-  return read_char(get_sft_idx(STDIN), check_break);
+  return read_char(get_sft_idx(STDIN), get_sft_idx(STDOUT), check_break);
 }
 
 /* reads a line (buffered, called by int21/ah=0ah, 3fh) */
@@ -399,9 +393,9 @@ void read_line(int sft_in, int sft_out, keyboard FAR * kp)
   {
     unsigned new_pos = stored_size;
     
-    c = read_char_check_break(sft_in);
+    c = read_char_check_break(sft_in, sft_out);
     if (c == 0)
-      c = (unsigned)read_char_check_break(sft_in) << 8;
+      c = (unsigned)read_char_check_break(sft_in, sft_out) << 8;
     switch (c)
     {
       case LF:
@@ -426,11 +420,11 @@ void read_line(int sft_in, int sft_out, keyboard FAR * kp)
       case F4:
         /* insert/delete up to character c */
         {
-          unsigned char c2 = read_char_check_break(sft_in);
+          unsigned char c2 = read_char_check_break(sft_in, sft_out);
           new_pos = stored_pos;
           if (c2 == 0)
           {
-            read_char_check_break(sft_in);
+            read_char_check_break(sft_in, sft_out);
           }
           else
           {

kernel/inthndlr.c

@@ -408,7 +408,7 @@ dispatch:
 
   /* Check for Ctrl-Break */
   if (break_ena || (lr.AH >= 1 && lr.AH <= 5) || (lr.AH >= 8 && lr.AH <= 0x0b))
-    check_handle_break();
+    check_handle_break(&syscon, -1);
 
   /* The dispatch handler                                         */
   switch (lr.AH)
@@ -435,8 +435,11 @@ dispatch:
 
       /* Auxiliary Input                                                      */
     case 0x03:
-      lr.AL = read_char(get_sft_idx(STDAUX), TRUE);
+    {
+      int sft_idx = get_sft_idx(STDAUX);
+      lr.AL = read_char(sft_idx, sft_idx, TRUE);
       break;
+    }
 
       /* Auxiliary Output                                                     */
     case 0x04:

kernel/proto.h

@@ -49,21 +49,18 @@ UWORD dskxfer(COUNT dsk, ULONG blkno, VOID FAR * buf, UWORD numblocks,
 void AllocateHMASpace (size_t lowbuffer, size_t highbuffer);
 
 /* break.c */
-#ifdef __WATCOMC__
+unsigned char check_handle_break(struct dhdr FAR **pdev, int sft_out);
-#pragma aux handle_break aborts;
-#endif
-int check_handle_break(void);
-void handle_break(struct dhdr FAR **pdev);
 
 /* chario.c */
 struct dhdr FAR *sft_to_dev(sft FAR *sft);
 long BinaryCharIO(struct dhdr FAR **pdev, size_t n, void FAR * bp,
                   unsigned command);
 int echo_char(int c, int sft_idx);
-int con_break(void);
+void echo_ctl_c(struct dhdr FAR **pdev, int sft_idx);
+int ndread(struct dhdr FAR **pdev);
 int StdinBusy(void);
 void con_flush(struct dhdr FAR **pdev);
-unsigned char read_char(int sft_idx, BOOL check_break);
+unsigned char read_char(int sft_in, int sft_out, BOOL check_break);
 unsigned char read_char_stdin(BOOL check_break);
 long cooked_read(struct dhdr FAR **pdev, size_t n, char FAR *bp);
 void read_line(int sft_in, int sft_out, keyboard FAR * kp);