cpython-launcher-c-mods-for-setuptools.3.7.patch

--- launcher.c.orig	2020-02-23 11:24:16.544939800 +0100
+++ launcher.c	2020-02-23 11:32:24.454773100 +0100
@@ -8,11 +8,71 @@
  * Curt Hagenlocher (job management)
  */
 
+#if defined(_MSC_VER)
+#ifdef NDEBUG
+// /Og (global optimizations), /Os (favor small code), /Oy (no frame pointers)
+#pragma optimize("gsy",on)
+
+// Note that merging the .rdata section will result in LARGER exe's if you using
+// MFC (esp. static link). If this is desirable, define _MERGE_RDATA_ in your project.
+#ifdef _MERGE_RDATA_
+#pragma comment(linker,"/merge:.rdata=.data")
+#endif // _MERGE_RDATA_
+
+#endif // NDEBUG
+#endif
+
 #include <windows.h>
 #include <shlobj.h>
 #include <stdio.h>
 #include <tchar.h>
 
+/* To build on MSYS2 use the following script:
+#!/usr/bin/env bash
+
+wget -c https://raw.githubusercontent.com/python/cpython/3.7/PC/launcher.c -O launcher.c
+patch -p0 < $(dirname ${BASH_SOURCE[0]})/cpython-launcher-c-mods-for-setuptools.3.7.patch
+RCFILE=$(dirname ${BASH_SOURCE[0]})/resources.rc
+[[ -f ${RCFILE} ]] && rm -f ${RCFILE}
+echo "#include \"winuser.h\""      > ${RCFILE}
+echo "1 RT_MANIFEST manifest.xml" >> ${RCFILE}
+for _BITS in 64 32; do
+  [[ -f resources-${_BITS}.res ]] && rm -f resources-${_BITS}.res
+  PATH=/mingw${_BITS}/bin:$PATH windres --input ${RCFILE} --output resources-${_BITS}.res --output-format=coff
+  for _TYPE in cli gui; do
+    if [[ ${_TYPE} == cli ]]; then
+      CPPFLAGS=
+      LDFLAGS=
+    else
+      CPPFLAGS="-D_WINDOWS -mwindows"
+      LDFLAGS="-mwindows"
+    fi
+    # You *could* use MSVC 2008 here, but you'd end up with much larger (~230k) executables.
+    # cl.exe -opt:nowin98 -D NDEBUG -D "GUI=0" -D "WIN32_LEAN_AND_MEAN" -ZI -Gy -MT -MERGE launcher.c -Os -link -MACHINE:x64 -SUBSYSTEM:CONSOLE version.lib advapi32.lib shell32.lib
+    PATH=/mingw${_BITS}/bin:$PATH gcc -O2 -DSCRIPT_WRAPPER -DUNICODE -D_UNICODE -DMINGW_HAS_SECURE_API ${CPPFLAGS} launcher.c -c -o ${_TYPE}-${_BITS}.o
+    PATH=/mingw${_BITS}/bin:$PATH gcc -Wl,-s --static -static-libgcc -municode ${LDFLAGS} ${_TYPE}-${_BITS}.o resources-${_BITS}.res -o ${_TYPE}-${_BITS}.exe
+  done
+done
+ls -l *.exe
+echo "Debug this from cmd.exe via:"
+echo "set PYLAUNCH_DEBUG=1"
+ */
+
+/* Previosuly GetFileVersionInfoW was used here, but I would rather save
+ * the 1.5k that costs. If we bring this back, add -lversion to the link
+ * command line.
+ */
+
+#define VERSION_HIGH 0
+#define VERSION_LOW 1
+
+/* Previously BUFSIZE was used for this but 256 is not enough for even 260
+ * ASCII characters and far too little for unicode (it is a char array, not
+ * a wchar_t array, though it needs to be even bigger than 260 wchar_ts as
+ * the source script file could contain UTF-8 or UTF-32 (wchar_t is 2-byte)
+ */
+#define SHEBANG_BUFSIZE 2048
+
 #define BUFSIZE 256
 #define MSGSIZE 1024
 
@@ -742,6 +802,7 @@
     { L"/usr/bin/env python", TRUE },
     { L"/usr/bin/python", FALSE },
     { L"/usr/local/bin/python", FALSE },
+    { L"python_d", FALSE },
     { L"python", FALSE },
     { NULL, FALSE },
 };
@@ -796,6 +857,25 @@
 
 static COMMAND path_command;
 
+#if !defined(_MSC_VER)
+errno_t _wdupenv_s_emulated(wchar_t **buffer,
+                            size_t *numberOfElements,
+                            const wchar_t *varname)
+{
+    size_t szreq;
+
+    errno_t err = _wgetenv_s(&szreq, NULL, 0, varname);
+    if (szreq == 0)
+        return 1;
+    *buffer = (wchar_t*) malloc(sizeof(wchar_t) * szreq);
+    if (!*buffer)
+        return 1;
+    err = _wgetenv_s(&szreq, *buffer, szreq, varname);
+    return err;
+}
+#define _wdupenv_s _wdupenv_s_emulated
+#endif
+
 static COMMAND * find_on_path(wchar_t * name)
 {
     wchar_t * pathext;
@@ -919,7 +999,7 @@
 
 static BOOL
 parse_shebang(wchar_t * shebang_line, int nchars, wchar_t ** command,
-              wchar_t ** suffix, BOOL *search)
+              wchar_t ** suffix, BOOL *search, wchar_t * argv0)
 {
     BOOL rc = FALSE;
     SHEBANG * vpp;
@@ -929,11 +1009,40 @@
     wchar_t * endp = shebang_line + nchars - 1;
     COMMAND * cp;
     wchar_t * skipped;
+    wchar_t tidied[_MAX_DRIVE+_MAX_DIR+_MAX_FNAME+_MAX_EXT] = L"";
 
     *command = NULL;    /* failure return */
     *suffix = NULL;
     *search = FALSE;
 
+    if ((shebang_line[0] != L'#') || (shebang_line[1] != L'!')) {
+        /* This is deliberately very similar to find_exe() in:
+         * https://raw.githubusercontent.com/pypa/setuptools/master/launcher.c
+         * I was tempted to use _wsplitpath_s twice to get the parent dir, but
+         * any change of behaviour here would cause big trouble.
+         */
+        wchar_t drive[_MAX_DRIVE];
+        wchar_t dir[_MAX_DIR];
+        wchar_t fname[_MAX_FNAME];
+        wchar_t ext[_MAX_EXT];
+        wchar_t * tmp, wc;
+        debug(L"parse_shebang called without a valid shebang %s (for argv0 %s)\n", shebang_line, argv0);
+        if (wcslen(argv0)-1 < _countof(tidied)) {
+            wcsncpy_s(tidied, _countof(tidied), argv0, _TRUNCATE);
+            tmp = &tidied[0];
+            while (wc = *tmp++) {
+                if (wc == L'/') tmp[-1] = L'\\';
+            }
+            _wsplitpath_s(tidied, drive, _countof(drive), dir, _countof(dir), fname, _countof(fname), ext, _countof(ext));
+            tmp = dir+wcslen(dir)-1;
+            if (*tmp == L'\\') tmp--;
+            while (*tmp != L'\\' && tmp>=dir) *tmp-- = 0;
+            _snwprintf_s(tidied, _countof(tidied), _TRUNCATE, L"#!%s%s%s", drive, dir, PYTHON_EXECUTABLE);
+            debug(L"invented shebang: %s\n", tidied);
+            shebang_line = tidied;
+        }
+    }
+
     if ((*shebang_line++ == L'#') && (*shebang_line++ == L'!')) {
         shebang_line = skip_whitespace(shebang_line);
         if (*shebang_line) {
@@ -947,6 +1056,7 @@
                      * "python".
                      */
                     *command = wcsstr(shebang_line, L"python");
+                    debug(L"found in builtin_virtual_paths: %s, command: %s\n", vpp->shebang, *command);
                     break;
                 }
             }
@@ -1072,10 +1182,13 @@
 validate_version(wchar_t * p)
 {
     /*
+    Optionally _d,
     Version information should start with the major version,
     Optionally followed by a period and a minor version,
     Optionally followed by a minus and one of 32 or 64.
     Valid examples:
+      _d
+      _d3
       2
       3
       2.7
@@ -1089,6 +1202,20 @@
     */
     BOOL result = (p != NULL); /* Default to False if null pointer. */
 
+    /* Skip _d for Windows debug. Interestingly, the name-script.py files from a release build
+       do not end up containing a shebang while debug builds have #!python_d */
+    if (result)
+        debug(L"validate_version: in: %ls\n", p);
+    if (result && p[0] == '_' && p[1] == 'd')
+	{
+        debug(L"validate_version: Windows _d shebang\n");
+		p += 2;
+	}
+    if (!*p)
+	{
+        debug(L"validate_version: No version number provided\n");
+        return TRUE;
+	}
     result = result && iswdigit(*p);  /* Result = False if first string element is not a digit. */
 
     while (result && iswdigit(*p))   /* Require a major version */
@@ -1171,7 +1298,7 @@
  */
     FILE * fp;
     errno_t rc = _wfopen_s(&fp, *argv, L"rb");
-    char buffer[BUFSIZE];
+    char buffer[SHEBANG_BUFSIZE];
     wchar_t shebang_line[BUFSIZE + 1];
     size_t read;
     char *p;
@@ -1188,7 +1315,7 @@
     INSTALLED_PYTHON * ip;
 
     if (rc == 0) {
-        read = fread(buffer, sizeof(char), BUFSIZE, fp);
+        read = fread(buffer, sizeof(char), SHEBANG_BUFSIZE, fp);
         debug(L"maybe_handle_shebang: read %zd bytes\n", read);
         fclose(fp);
 
@@ -1213,7 +1340,7 @@
                   bom->code_page);
             start = &buffer[bom->length];
         }
-        p = find_terminator(start, BUFSIZE, bom);
+        p = find_terminator(start, SHEBANG_BUFSIZE, bom);
         /*
          * If no CR or LF was found in the heading,
          * we assume it's not a shebang file.
@@ -1297,10 +1424,10 @@
             if (nchars > 0) {
                 shebang_line[--nchars] = L'\0';
                 is_virt = parse_shebang(shebang_line, nchars, &command,
-                                        &suffix, &search);
+                                        &suffix, &search, *argv);
                 if (command != NULL) {
                     debug(L"parse_shebang: found command: %ls\n", command);
-                    if (!is_virt) {
+                    if (!is_virt) { /* || !wcsncmp(command, L"python_d", 8)) { */
                         invoke_child(command, suffix, cmdline);
                     }
                     else {
@@ -1409,7 +1536,7 @@
 
     get_version_info(version_text, MAX_PATH);
     fwprintf(stdout, L"\
-Python Launcher for Windows Version %ls\n\n", version_text);
+Python Launcher for Windows (Anaconda/Setuptools variant) Version %ls\n\n", version_text);
     fwprintf(stdout, L"\
 usage:\n\
 %ls [launcher-args] [python-args] script [script-args]\n\n", argv[0]);
@@ -1584,6 +1711,7 @@
     int newlen;
     HRESULT hr;
     int index;
+    int quoted = 0;
 #else
     HRESULT hr;
     int index;
@@ -1624,6 +1752,7 @@
     }
 #endif
     argv0 = get_process_name();
+/*
     size = GetFileVersionInfoSizeW(argv0, &size);
     if (size == 0) {
         winerror(GetLastError(), message, MSGSIZE);
@@ -1649,6 +1778,9 @@
             free(version_data);
         }
     }
+*/
+    version_high = VERSION_HIGH;
+    version_low = VERSION_LOW;
 
 #if defined(VENV_REDIRECT)
     /* Allocate some extra space for new filenames */
@@ -1731,13 +1863,24 @@
     locate_wrapped_script();
 
     /* Add the wrapped script to the start of command */
-    newlen = wcslen(wrapped_script_path) + wcslen(command) + 2; /* ' ' + NUL */
+    p = wcsrchr(wrapped_script_path, L' ');
+    if (p != NULL)
+        quoted = 1;
+    newlen = wcslen(wrapped_script_path) + wcslen(command) + 2 + (2 * quoted); /* ' ' + NUL */
     newcommand = malloc(sizeof(wchar_t) * newlen);
     if (!newcommand) {
         error(RC_NO_MEMORY, L"Could not allocate new command line");
     }
     else {
-        wcscpy_s(newcommand, newlen, wrapped_script_path);
+	    /* This probably breaks already-quoted things. */
+        newcommand[0] = L'\0';
+        if (quoted) {
+            wcscpy_s(newcommand, newlen, L"\"");
+        }
+        wcscat_s(newcommand, newlen, wrapped_script_path);
+        if (quoted) {
+            wcscat_s(newcommand, newlen, L"\"");
+        }
         wcscat_s(newcommand, newlen, L" ");
         wcscat_s(newcommand, newlen, command);
         debug(L"Running wrapped script with command line '%ls'\n", newcommand);