Backport of bug

457466: "popenx() argument mangling hangs python" [Win9x only]."

Can't test this myself, but MarkH sez it's ok.

diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 1733d870ce3d67f66ec52c82a30483b7f345131a..f491c47aad9cd27d61c0b4b5ea0d83c8cdb2a90d 100644 (file)
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -2422,9 +2422,15 @@ _PyPopenCreateProcess(char *cmdstring,
 
                        s2 = (char *)_alloca(x);
                        ZeroMemory(s2, x);
+                       /* To maintain correct argument passing semantics,
+                          we pass the command-line as it stands, and allow
+                          quoting to be applied.  w9xpopen.exe will then
+                          use its argv vector, and re-quote the necessary
+                          args for the ultimate child process.
+                       */
                        sprintf(
                                s2,
-                               "%s \"%s%s%s\"",
+                               "\"%s\" %s%s%s",
                                modulepath,
                                s1,
                                s3,

diff --git a/PC/w9xpopen.c b/PC/w9xpopen.c
index d96d0f5e5876dd0c0070803a739534df06d4cbf3..31448fd81c798b698f32be53f711d7588d9fe6a8 100644 (file)
--- a/PC/w9xpopen.c
+++ b/PC/w9xpopen.c
@@ -16,9 +16,10 @@
 
 #define WINDOWS_LEAN_AND_MEAN
 #include <windows.h>
+#include <stdio.h>
 
 const char *usage =
-"This program is used by Python's os.pipe function to\n"
+"This program is used by Python's os.popen function to\n"
 "to work around a limitation in Windows 95/98.  It is\n"
 "not designed to be used as stand-alone program.";
 
@@ -28,11 +29,56 @@ int main(int argc, char *argv[])
     STARTUPINFO si;
     PROCESS_INFORMATION pi;
     DWORD exit_code=0;
+    int cmdlen = 0;
+    int i;
+    char *cmdline, *cmdlinefill;
 
-    if (argc != 2) {
-        MessageBox(NULL, usage, argv[0], MB_OK);
+    if (argc < 2) {
+        if (GetFileType(GetStdHandle(STD_INPUT_HANDLE))==FILE_TYPE_CHAR)
+            /* Attached to a console, and therefore not executed by Python
+               Display a message box for the inquisitive user
+            */
+            MessageBox(NULL, usage, argv[0], MB_OK);
+        else {
+            /* Eeek - executed by Python, but args are screwed!
+               Write an error message to stdout so there is at
+               least some clue for the end user when it appears
+               in their output.
+               A message box would be hidden and blocks the app.
+             */
+            fprintf(stdout, "Internal popen error - no args specified\n%s\n", usage);
+        }
         return 1;
     }
+    /* Build up the command-line from the args.
+       Args with a space are quoted, existing quotes are escaped.
+       To keep things simple calculating the buffer size, we assume
+       every character is a quote - ie, we allocate double what we need
+       in the worst case.  As this is only double the command line passed
+       to us, there is a good chance this is reasonably small, so the total 
+       allocation will almost always be < 512 bytes.
+    */
+    for (i=1;i<argc;i++)
+        cmdlen += strlen(argv[i])*2 + 3; /* one space, maybe 2 quotes */
+    cmdline = cmdlinefill = (char *)malloc(cmdlen+1);
+    if (cmdline == NULL)
+        return -1;
+    for (i=1;i<argc;i++) {
+        const char *arglook;
+        int bQuote = strchr(argv[i], ' ') != NULL;
+        if (bQuote)
+            *cmdlinefill++ = '"';
+        /* escape quotes */
+        for (arglook=argv[i];*arglook;arglook++) {
+            if (*arglook=='"')
+                *cmdlinefill++ = '\\';
+            *cmdlinefill++ = *arglook;
+        }
+        if (bQuote)
+            *cmdlinefill++ = '"';
+        *cmdlinefill++ = ' ';
+    }
+    *cmdlinefill = '\0';
 
     /* Make child process use this app's standard files. */
     ZeroMemory(&si, sizeof si);
@@ -43,13 +89,15 @@ int main(int argc, char *argv[])
     si.hStdError = GetStdHandle(STD_ERROR_HANDLE);
 
     bRet = CreateProcess(
-        NULL, argv[1],
+        NULL, cmdline,
         NULL, NULL,
         TRUE, 0,
         NULL, NULL,
         &si, &pi
         );
 
+    free(cmdline);
+
     if (bRet) {
         if (WaitForSingleObject(pi.hProcess, INFINITE) != WAIT_FAILED) {
            GetExitCodeProcess(pi.hProcess, &exit_code);