Message-ID: <39847B14.9330C86A@softhome.net>
Date: Sun, 30 Jul 2000 20:59:32 +0200
From: Laurynas Biveinis <lauras AT softhome DOT net>
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To: DJGPP Workers <djgpp-workers AT delorie DOT com>
Subject: Another step to symlinks
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Reply-To: djgpp-workers AT delorie DOT com

This patch to dosexec.c makes library calls launch other
DJGPP programs only by !proxy. This allows to pass argv[0]
correctly to symlinked programs.

IIRC, Eli has said that DJGPP didn't use !proxy only because
there might be some subtle bug lurking somewhere. If there is
any, let's face it.

Laurynas

Index: dosexec.c
===================================================================
RCS file: /cvs/djgpp/djgpp/src/libc/dos/process/dosexec.c,v
retrieving revision 1.8
diff -u -r1.8 dosexec.c
--- dosexec.c	2000/07/15 14:19:47	1.8
+++ dosexec.c	2000/07/30 18:59:37
@@ -614,87 +614,81 @@
 
   /* Can't call any functions that use the transfer buffer beyond
      this point: they will overwrite the data already in __tb.  */
+
   tbuf_beg = tbuf_ptr = __tb;
   tbuf_len = _go32_info_block.size_of_transfer_buffer;
   tbuf_end = tbuf_ptr + tbuf_len - 1;
 
-  /* If called from `system' and we have a command line shorter
-     than the DOS limit, we don't need to use !proxy at all.
-     Note that v1.x programs are always run through !proxy,
-     to prevent go32.exe from printing its copyright line. */
-  if (!__dosexec_in_system || !v2_0 || cmdp - cmdline > CMDLEN_LIMIT)
+  /* Starting from DJGPP v2.04, programs are always run through !proxy.
+     This allows correctly handle symlinks to .exes. */
+  if (!check_talloc(found_si ?
+		    type->stubinfo->struct_length : 0
+		    + (argc+1)*sizeof(short)))
   {
-    if (!check_talloc(found_si ?
-		      type->stubinfo->struct_length : 0
-		      + (argc+1)*sizeof(short)))
-    {
-      argv[0] = save_argv0;
-      return -1;
-    }
-    if (found_si)
-    {
-      si_la = talloc(type->stubinfo->struct_length);
-      si_off = si_la - tbuf_beg;
-      dosmemput(sip, type->stubinfo->struct_length, si_la);
-    }
+    argv[0] = save_argv0;
+    return -1;
+  }
+  if (found_si)
+  {
+    si_la = talloc(type->stubinfo->struct_length);
+    si_off = si_la - tbuf_beg;
+    dosmemput(sip, type->stubinfo->struct_length, si_la);
+  }
 
-    rm_off = argv_off = talloc((argc+1) * sizeof(short)) - tbuf_beg;
+  rm_off = argv_off = talloc((argc+1) * sizeof(short)) - tbuf_beg;
 #if 0
-    /* `alloca' could be dangerous with long command lines.  We
-       will instead move the offsets one by one with `_farpokew'.  */
-    rm_argv = (short *)alloca((argc+1) * sizeof(short));
+  /* `alloca' could be dangerous with long command lines.  We
+     will instead move the offsets one by one with `_farpokew'.  */
+  rm_argv = (short *)alloca((argc+1) * sizeof(short));
 #endif
+
+  for (i=0; i<argc; i++)
+  {
+    char *pargv = argv[i];
+    int sl = strlen(pargv) + 1;
+    unsigned long q;
 
-    for (i=0; i<argc; i++)
+    if (check_talloc(sl))
     {
-      char *pargv = argv[i];
-      int sl = strlen(pargv) + 1;
-      unsigned long q;
-
-      if (check_talloc(sl))
-      {
-	q = talloc(sl);
-	dosmemput(pargv, sl, q);
-	_farpokew(_dos_ds, tbuf_beg + argv_off, (q - tbuf_beg) & 0xffff);
-	argv_off += sizeof(short);
-      }
-      else	/* not enough space to pass args */
-      {
-	argv[0] = save_argv0;
-	return -1;
-      }
+      q = talloc(sl);
+      dosmemput(pargv, sl, q);
+      _farpokew(_dos_ds, tbuf_beg + argv_off, (q - tbuf_beg) & 0xffff);
+      argv_off += sizeof(short);
     }
-
-    _farpokew (_dos_ds, tbuf_beg + argv_off, 0);
-    argv_off += sizeof(short);
-
-    argv[0] = save_argv0;
-    /* Environment variables are all malloced.  */
-    proxy_cmdline = (char *)malloc (34);
-    if (!proxy_cmdline)
-      return -1;
-    
-    sprintf(proxy_cmdline, "%s=%04x %04x %04x %04x %04x",
-	     __PROXY, argc,
-	    (unsigned)(tbuf_beg >> 4), rm_off & 0xffff,
-	    (unsigned)(tbuf_beg >> 4), si_off & 0xffff);
-    if (!found_si)
-      proxy_cmdline[22] = 0; /* remove stubinfo information */
-
-    if (__dosexec_in_system && v2_0)
-      pproxy = proxy_cmdline;
-    else
+    else	/* not enough space to pass args */
     {
-      /* `proxy_cmdline looks like an environment variable " !proxy=value".
-         This is used as the REAL command line specification by 2.01
-	 and later executables when called by `system'.  But if that's
-	 not the case, we need a blank instead of the `='.  */
-      proxy_cmdline[__PROXY_LEN] = ' ';
-      pcmd = proxy_cmdline;
+      argv[0] = save_argv0;
+      return -1;
     }
   }
+
+  _farpokew (_dos_ds, tbuf_beg + argv_off, 0);
+  argv_off += sizeof(short);
+
+  argv[0] = save_argv0;
+  /* Environment variables are all malloced.  */
+  proxy_cmdline = (char *)malloc (34);
+  if (!proxy_cmdline)
+    return -1;
+  
+  sprintf(proxy_cmdline, "%s=%04x %04x %04x %04x %04x",
+    __PROXY, argc,
+   (unsigned)(tbuf_beg >> 4), rm_off & 0xffff,
+   (unsigned)(tbuf_beg >> 4), si_off & 0xffff);
+  if (!found_si)
+    proxy_cmdline[22] = 0; /* remove stubinfo information */
+
+  if (__dosexec_in_system && v2_0)
+    pproxy = proxy_cmdline;
   else
-    argv[0] = save_argv0;
+  {
+    /* `proxy_cmdline looks like an environment variable " !proxy=value".
+        This is used as the REAL command line specification by 2.01
+        and later executables when called by `system'.  But if that's
+        not the case, we need a blank instead of the `='.  */
+    proxy_cmdline[__PROXY_LEN] = ' ';
+    pcmd = proxy_cmdline;
+  }
 
   retval = direct_exec_tail(rpath, pcmd, envp, pproxy, lfn);
   if (proxy_cmdline)