Integrate change #12747 from maintperl;

finishing touches to system() fixes on windows:
* detect cmd shell correctly even if it had full path in it
* more quoting needed for single-arg system if the argument
  really had multiple quoted arguments within it
* be smarter about not calling the shell when the executable
  has spaces, but otherwise does not need shell involvement
* add a testsuite (windows-specific currently)

p4raw-link: @12747 on //depot/maint-5.6/perl: 2bab9a31df533a6c8068e22c59c8dfb29a47c95e

p4raw-id: //depot/perl@12748
p4raw-branched: from //depot/maint-5.6/perl@12746 'branch in'
	t/op/system.t t/op/system_tests
p4raw-edited: from //depot/maint-5.6/perl@12746 'ignore'
	pod/perltodo.pod (@8171..) MANIFEST (@11426..)
p4raw-integrated: from //depot/maint-5.6/perl@12746 'merge in'
	win32/win32.c (@12725..)

1 files changed, 97 insertions, 37 deletions

diff --git a/win32/win32.c b/win32/win32.c
index f50436e6bf..b23ce65c36 100644
--- a/win32/win32.c
+++ b/win32/win32.c
@@ -586,6 +586,30 @@ do_aspawn(void *vreally, void **vmark, void **vsp)
     return (status);
 }
 
+/* returns pointer to the next unquoted space or the end of the string */
+static char*
+find_next_space(const char *s)
+{
+    bool in_quotes = FALSE;
+    while (*s) {
+	/* ignore doubled backslashes, or backslash+quote */
+	if (*s == '\\' && (s[1] == '\\' || s[1] == '"')) {
+	    s += 2;
+	}
+	/* keep track of when we're within quotes */
+	else if (*s == '"') {
+	    s++;
+	    in_quotes = !in_quotes;
+	}
+	/* break it up only at spaces that aren't in quotes */
+	else if (!in_quotes && isSPACE(*s))
+	    return (char*)s;
+	else
+	    s++;
+    }
+    return (char*)s;
+}
+
 int
 do_spawn2(char *cmd, int exectype)
 {
@@ -605,27 +629,11 @@ do_spawn2(char *cmd, int exectype)
 	strcpy(cmd2, cmd);
 	a = argv;
 	for (s = cmd2; *s;) {
-	    bool in_quotes = FALSE;
 	    while (*s && isSPACE(*s))
 		s++;
 	    if (*s)
 		*(a++) = s;
-	    while (*s) {
-		/* ignore doubled backslashes, or backslash+quote */
-		if (*s == '\\' && (s[1] == '\\' || s[1] == '"')) {
-		    s += 2;
-		}
-		/* keep track of when we're within quotes */
-		else if (*s == '"') {
-		    s++;
-		    in_quotes = !in_quotes;
-		}
-		/* break it up only at spaces that aren't in quotes */
-		else if (!in_quotes && isSPACE(*s))
-		    break;
-		else
-		    s++;
-	    }
+	    s = find_next_space(s);
 	    if (*s)
 		*s++ = '\0';
 	}
@@ -3092,7 +3100,7 @@ win32_chmod(const char *path, int mode)
 
 
 static char *
-create_command_line(const char *cmdname, const char * const *args)
+create_command_line(char *cname, STRLEN clen, const char * const *args)
 {
     dTHX;
     int index, argc;
@@ -3102,7 +3110,7 @@ create_command_line(const char *cmdname, const char * const *args)
     bool bat_file = FALSE;
     bool cmd_shell = FALSE;
     bool extra_quotes = FALSE;
-    char *cname = (char*)cmdname;
+    bool quote_next = FALSE;
 
     if (!cname)
 	cname = (char*)args[0];
@@ -3119,9 +3127,13 @@ create_command_line(const char *cmdname, const char * const *args)
      * to the string, if the first argument is either "cmd.exe" or "cmd",
      * and there were at least two or more arguments passed to cmd.exe
      * (not including switches).
+     * XXX the above rules (from "cmd /?") don't seem to be applied
+     * always, making for the convolutions below :-(
      */
     if (cname) {
-	STRLEN clen = strlen(cname);
+	if (!clen)
+	    clen = strlen(cname);
+
 	if (clen > 4
 	    && (stricmp(&cname[clen-4], ".bat") == 0
 		|| (IsWinNT() && stricmp(&cname[clen-4], ".cmd") == 0)))
@@ -3129,11 +3141,19 @@ create_command_line(const char *cmdname, const char * const *args)
 	    bat_file = TRUE;
 	    len += 3;
 	}
-	else if (stricmp(cname, "cmd.exe") == 0
-		 || stricmp(cname, "cmd") == 0)
-	{
-	    cmd_shell = TRUE;
-	    len += 3;
+	else {
+	    char *exe = strrchr(cname, '/');
+	    char *exe2 = strrchr(cname, '\\');
+	    if (exe2 > exe)
+		exe = exe2;
+	    if (exe)
+		++exe;
+	    else
+		exe = cname;
+	    if (stricmp(exe, "cmd.exe") == 0 || stricmp(exe, "cmd") == 0) {
+		cmd_shell = TRUE;
+		len += 3;
+	    }
 	}
     }
 
@@ -3175,6 +3195,13 @@ create_command_line(const char *cmdname, const char * const *args)
 		i++;
 	    }
 	}
+	else if (quote_next) {
+	    /* ok, we know the argument already has quotes; see if it
+	     * really is multiple arguments pretending to be one and
+	     * force a set of quotes around it */
+	    if (*find_next_space(arg))
+		do_quote = 1;
+	}
 
 	if (do_quote)
 	    *ptr++ = '"';
@@ -3190,11 +3217,20 @@ create_command_line(const char *cmdname, const char * const *args)
 
     	if (!extra_quotes
 	    && cmd_shell
-	    && (stricmp(arg, "/x/c") == 0 || stricmp(arg, "/c") == 0)
-	    && (argc-1 > index+1))   /* two or more arguments to cmd.exe? */
+	    && (stricmp(arg, "/x/c") == 0 || stricmp(arg, "/c") == 0))
 	{
-	    *ptr++ = '"';
-	    extra_quotes = TRUE;
+	    /* is there a next argument? */
+	    if (args[index+1]) {
+		/* are there two or more next arguments? */
+		if (args[index+2]) {
+		    *ptr++ = '"';
+		    extra_quotes = TRUE;
+		}
+		else {
+		    /* single argument, force quoting if unquoted */
+		    quote_next = TRUE;
+		}
+	    }
 	}
     }
 
@@ -3384,9 +3420,30 @@ win32_spawnvp(int mode, const char *cmdname, const char *const *argv)
     STARTUPINFO StartupInfo;
     PROCESS_INFORMATION ProcessInformation;
     DWORD create = 0;
-
-    char *cmd = create_command_line(cmdname, argv);
+    char *cmd;
     char *fullcmd = Nullch;
+    char *cname = (char *)cmdname;
+    STRLEN clen = 0;
+
+    if (cname) {
+	clen = strlen(cname);
+	/* if command name contains dquotes, must remove them */
+	if (strchr(cname, '"')) {
+	    cmd = cname;
+	    New(0,cname,clen+1,char);
+	    clen = 0;
+	    while (*cmd) {
+		if (*cmd != '"') {
+		    cname[clen] = *cmd;
+		    ++clen;
+		}
+		++cmd;
+	    }
+	    cname[clen] = '\0';
+	}
+    }
+
+    cmd = create_command_line(cname, clen, argv);
 
     env = PerlEnv_get_childenv();
     dir = PerlEnv_get_childdir();
@@ -3433,9 +3490,9 @@ win32_spawnvp(int mode, const char *cmdname, const char *const *argv)
     }
 
     DEBUG_p(PerlIO_printf(Perl_debug_log, "Spawning [%s] with [%s]\n",
-			  cmdname,cmd));
+			  cname,cmd));
 RETRY:
-    if (!CreateProcess(cmdname,		/* search PATH to find executable */
+    if (!CreateProcess(cname,		/* search PATH to find executable */
 		       cmd,		/* executable, and its arguments */
 		       NULL,		/* process attributes */
 		       NULL,		/* thread attributes */
@@ -3453,12 +3510,14 @@ RETRY:
 	 * jump through our own hoops by picking out the path
 	 * we really want it to use. */
 	if (!fullcmd) {
-	    fullcmd = qualified_path(cmdname);
+	    fullcmd = qualified_path(cname);
 	    if (fullcmd) {
-		cmdname = fullcmd;
+		if (cname != cmdname)
+		    Safefree(cname);
+		cname = fullcmd;
 		DEBUG_p(PerlIO_printf(Perl_debug_log,
 				      "Retrying [%s] with same args\n",
-				      cmdname));
+				      cname));
 		goto RETRY;
 	    }
 	}
@@ -3491,7 +3550,8 @@ RETVAL:
     PerlEnv_free_childenv(env);
     PerlEnv_free_childdir(dir);
     Safefree(cmd);
-    Safefree(fullcmd);
+    if (cname != cmdname)
+	Safefree(cname);
     return ret;
 #endif
 }