Date: Fri, 13 Jul 2001 16:16:22 +0300
From: "Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
Sender: halo1 AT zahav DOT net DOT il
To: djgpp-workers AT delorie DOT com
Message-Id: <3405-Fri13Jul2001161622+0300-eliz@is.elta.co.il>
X-Mailer: Emacs 20.6 (via feedmail 8.3.emacs20_6 I) and Blat ver 1.8.9
Subject: Long command lines passed to a debuggee
Reply-To: djgpp-workers AT delorie DOT com

It looks like no one actually tried to use the modified v2loadimage,
because it didn't work: it put the truncated command line in the wrong
place, and it turns out that the use of the transfer buffer was not a
good idea (v2loadimage doesn't actually start the program, so by the
time it is started, some other code in the debugger can overwrite the
transfer buffer).

The patches to fix that are below.  I've committed them (because the
new version cannot possibly be worse than the old ;-), but if someone
has comments on the new code, please speak up.

(I also needed to fix c1args.c, to prevent it from interpreting 0xff
in the first byte of the command tail as a sign that CMDLINE is used.
That change is also committed.)

With these changes, and a suitable change in ed.c, FSDB supports long
commands.


Index: src/debug/common/v2load.c
===================================================================
RCS file: /cvs/djgpp/djgpp/src/debug/common/v2load.c,v
retrieving revision 1.8
diff -u -p -r1.8 v2load.c
--- src/debug/common/v2load.c	2001/07/11 17:01:15	1.8
+++ src/debug/common/v2load.c	2001/07/13 12:46:38
@@ -104,12 +104,12 @@ static char proxy_string[] = " !proxy";
 
 static int
 make_proxy_var(const char *program, const char *cmdline,
-               unsigned long tbuf, size_t tb_len,
-               size_t *proxy_argc, size_t *tb_space)
+               unsigned long *tbuf, size_t *tb_space, size_t *proxy_argc)
 {
   size_t argc;
   const char *beg, *end;
   char proxy[48];
+  int max_dos_mem;
 
   /* Include the program name, a null terminator, and offset pointer
      in the argument count.  */  
@@ -117,7 +117,7 @@ make_proxy_var(const char *program, cons
   *tb_space = strlen(program) + 1 + sizeof(short);
 
   /* Got arguments? */
-  while (*cmdline && (*tb_space <= tb_len))
+  while (*cmdline)
   {
     cmdline = get_arg(cmdline, &beg, &end);
     /* Add in the space needed for the command, a null terminator
@@ -125,17 +125,16 @@ make_proxy_var(const char *program, cons
     *tb_space += (end - beg) + 1 + sizeof(short);
     ++argc;
   }
-  /* If the last arg would cause an overrun, don't include it.  */
-  if (*tb_space > tb_len)
-  {
-    --argc;
-    *tb_space -= (end - beg) - 1 - sizeof(short);
-  }
 
+  *tbuf = __dpmi_allocate_dos_memory ((*tb_space + 15) >> 4, &max_dos_mem);
+  if (*tbuf == -1)
+    return 0;
+
+  *tbuf <<= 4;
   *proxy_argc = argc;
 
   sprintf(proxy, "%s=%04x %04lx %04lx", proxy_string, (unsigned int)argc,
-                                          tbuf / 16, tbuf & 0x0f);
+                                        *tbuf / 16, *tbuf & 0x0f);
   putenv(proxy);
 
   return 1;
@@ -188,8 +187,10 @@ int v2loadimage(const char *program, con
   __dpmi_meminfo memblock;
   unsigned new_env_selector;
   char true_name[FILENAME_MAX];
-  size_t proxy_argc, proxy_space;
+  size_t proxy_argc;
   int proxy_mode;
+  unsigned long tbuf;
+  size_t tbuf_len;
 
   _truename(program, true_name);
 
@@ -270,8 +271,10 @@ int v2loadimage(const char *program, con
   /* Create the proxy variable now so the child's environment
      has the correct size.  */
   if (proxy_mode)
-    make_proxy_var(program, cmdline + 1, __tb, __tb_size,
-                   &proxy_argc, &proxy_space);
+  {
+    if (!make_proxy_var(program, cmdline + 1, &tbuf, &tbuf_len, &proxy_argc))
+      return -1;
+  }
 
   si.env_size = 0;
   for (i=0; environ[i]; i++)
@@ -406,14 +409,14 @@ int v2loadimage(const char *program, con
     unsigned char cmd_len;
 
     /* Setup the transfer buffer with proxy arguments.  */
-    make_proxy_buffer(program, cmdline + 1, proxy_argc, __tb, __tb_size);
+    make_proxy_buffer(program, cmdline + 1, proxy_argc, tbuf, tbuf_len);
 
     /* Provide a fallback command line in case the debugee has disabled
        the proxy method.  */
     cmd_len = __strnlen(cmdline + 1, 126);
-    _farpokeb(my_ds, si.psp_selector + 128, cmd_len);
-    movedata(my_ds, (unsigned)(cmdline + 1), si.psp_selector, 128 + 1, cmd_len);
-    _farpokeb(my_ds, si.psp_selector + 128 + 1 + cmd_len, '\r');
+    _farpokeb(si.psp_selector, 128, cmd_len);
+    movedata(my_ds, (unsigned)(cmdline + 1), si.psp_selector, 128+1, cmd_len);
+    _farpokeb(si.psp_selector, 128 + 1 + cmd_len, '\r');
   }
   else
     /* copy command arguments into debug process */