cpython/PC/launcher.c

1567 lines
50 KiB
C

/*
* Copyright (C) 2011-2013 Vinay Sajip.
* Licensed to PSF under a contributor agreement.
*
* Based on the work of:
*
* Mark Hammond (original author of Python version)
* Curt Hagenlocher (job management)
*/
#include <windows.h>
#include <shlobj.h>
#include <stdio.h>
#include <tchar.h>
#define BUFSIZE 256
#define MSGSIZE 1024
/* Build options. */
#define SKIP_PREFIX
#define SEARCH_PATH
/* Error codes */
#define RC_NO_STD_HANDLES 100
#define RC_CREATE_PROCESS 101
#define RC_BAD_VIRTUAL_PATH 102
#define RC_NO_PYTHON 103
#define RC_NO_MEMORY 104
/*
* SCRIPT_WRAPPER is used to choose between two variants of an executable built
* from this source file. If not defined, the PEP 397 Python launcher is built;
* if defined, a script launcher of the type used by setuptools is built, which
* looks for a script name related to the executable name and runs that script
* with the appropriate Python interpreter.
*
* SCRIPT_WRAPPER should be undefined in the source, and defined in a VS project
* which builds the setuptools-style launcher.
*/
#if defined(SCRIPT_WRAPPER)
#define RC_NO_SCRIPT 105
#endif
/* Just for now - static definition */
static FILE * log_fp = NULL;
static wchar_t *
skip_whitespace(wchar_t * p)
{
while (*p && isspace(*p))
++p;
return p;
}
static void
debug(wchar_t * format, ...)
{
va_list va;
if (log_fp != NULL) {
va_start(va, format);
vfwprintf_s(log_fp, format, va);
}
}
static void
winerror(int rc, wchar_t * message, int size)
{
FormatMessageW(
FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, rc, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
message, size, NULL);
}
static void
error(int rc, wchar_t * format, ... )
{
va_list va;
wchar_t message[MSGSIZE];
wchar_t win_message[MSGSIZE];
int len;
va_start(va, format);
len = _vsnwprintf_s(message, MSGSIZE, _TRUNCATE, format, va);
if (rc == 0) { /* a Windows error */
winerror(GetLastError(), win_message, MSGSIZE);
if (len >= 0) {
_snwprintf_s(&message[len], MSGSIZE - len, _TRUNCATE, L": %ls",
win_message);
}
}
#if !defined(_WINDOWS)
fwprintf(stderr, L"%ls\n", message);
#else
MessageBox(NULL, message, TEXT("Python Launcher is sorry to say ..."),
MB_OK);
#endif
exit(rc);
}
/*
* This function is here to simplify memory management
* and to treat blank values as if they are absent.
*/
static wchar_t * get_env(wchar_t * key)
{
/* This is not thread-safe, just like getenv */
static wchar_t buf[BUFSIZE];
DWORD result = GetEnvironmentVariableW(key, buf, BUFSIZE);
if (result >= BUFSIZE) {
/* Large environment variable. Accept some leakage */
wchar_t *buf2 = (wchar_t*)malloc(sizeof(wchar_t) * (result+1));
if (buf2 == NULL) {
error(RC_NO_MEMORY, L"Could not allocate environment buffer");
}
GetEnvironmentVariableW(key, buf2, result);
return buf2;
}
if (result == 0)
/* Either some error, e.g. ERROR_ENVVAR_NOT_FOUND,
or an empty environment variable. */
return NULL;
return buf;
}
#if defined(_WINDOWS)
#define PYTHON_EXECUTABLE L"pythonw.exe"
#else
#define PYTHON_EXECUTABLE L"python.exe"
#endif
#define MAX_VERSION_SIZE 4
typedef struct {
wchar_t version[MAX_VERSION_SIZE]; /* m.n */
int bits; /* 32 or 64 */
wchar_t executable[MAX_PATH];
} INSTALLED_PYTHON;
/*
* To avoid messing about with heap allocations, just assume we can allocate
* statically and never have to deal with more versions than this.
*/
#define MAX_INSTALLED_PYTHONS 100
static INSTALLED_PYTHON installed_pythons[MAX_INSTALLED_PYTHONS];
static size_t num_installed_pythons = 0;
/*
* To hold SOFTWARE\Python\PythonCore\X.Y...\InstallPath
* The version name can be longer than MAX_VERSION_SIZE, but will be
* truncated to just X.Y for comparisons.
*/
#define IP_BASE_SIZE 40
#define IP_VERSION_SIZE 8
#define IP_SIZE (IP_BASE_SIZE + IP_VERSION_SIZE)
#define CORE_PATH L"SOFTWARE\\Python\\PythonCore"
static wchar_t * location_checks[] = {
L"\\",
L"\\PCBuild\\win32\\",
L"\\PCBuild\\amd64\\",
// To support early 32bit versions of Python that stuck the build binaries
// directly in PCBuild...
L"\\PCBuild\\",
NULL
};
static INSTALLED_PYTHON *
find_existing_python(wchar_t * path)
{
INSTALLED_PYTHON * result = NULL;
size_t i;
INSTALLED_PYTHON * ip;
for (i = 0, ip = installed_pythons; i < num_installed_pythons; i++, ip++) {
if (_wcsicmp(path, ip->executable) == 0) {
result = ip;
break;
}
}
return result;
}
static void
locate_pythons_for_key(HKEY root, REGSAM flags)
{
HKEY core_root, ip_key;
LSTATUS status = RegOpenKeyExW(root, CORE_PATH, 0, flags, &core_root);
wchar_t message[MSGSIZE];
DWORD i;
size_t n;
BOOL ok;
DWORD type, data_size, attrs;
INSTALLED_PYTHON * ip, * pip;
wchar_t ip_version[IP_VERSION_SIZE];
wchar_t ip_path[IP_SIZE];
wchar_t * check;
wchar_t ** checkp;
wchar_t *key_name = (root == HKEY_LOCAL_MACHINE) ? L"HKLM" : L"HKCU";
if (status != ERROR_SUCCESS)
debug(L"locate_pythons_for_key: unable to open PythonCore key in %ls\n",
key_name);
else {
ip = &installed_pythons[num_installed_pythons];
for (i = 0; num_installed_pythons < MAX_INSTALLED_PYTHONS; i++) {
status = RegEnumKeyW(core_root, i, ip_version, IP_VERSION_SIZE);
if (status != ERROR_SUCCESS) {
if (status != ERROR_NO_MORE_ITEMS) {
/* unexpected error */
winerror(status, message, MSGSIZE);
debug(L"Can't enumerate registry key for version %ls: %ls\n",
ip_version, message);
}
break;
}
else {
wcsncpy_s(ip->version, MAX_VERSION_SIZE, ip_version,
MAX_VERSION_SIZE-1);
_snwprintf_s(ip_path, IP_SIZE, _TRUNCATE,
L"%ls\\%ls\\InstallPath", CORE_PATH, ip_version);
status = RegOpenKeyExW(root, ip_path, 0, flags, &ip_key);
if (status != ERROR_SUCCESS) {
winerror(status, message, MSGSIZE);
// Note: 'message' already has a trailing \n
debug(L"%ls\\%ls: %ls", key_name, ip_path, message);
continue;
}
data_size = sizeof(ip->executable) - 1;
status = RegQueryValueExW(ip_key, NULL, NULL, &type,
(LPBYTE)ip->executable, &data_size);
RegCloseKey(ip_key);
if (status != ERROR_SUCCESS) {
winerror(status, message, MSGSIZE);
debug(L"%ls\\%ls: %ls\n", key_name, ip_path, message);
continue;
}
if (type == REG_SZ) {
data_size = data_size / sizeof(wchar_t) - 1; /* for NUL */
if (ip->executable[data_size - 1] == L'\\')
--data_size; /* reg value ended in a backslash */
/* ip->executable is data_size long */
for (checkp = location_checks; *checkp; ++checkp) {
check = *checkp;
_snwprintf_s(&ip->executable[data_size],
MAX_PATH - data_size,
MAX_PATH - data_size,
L"%ls%ls", check, PYTHON_EXECUTABLE);
attrs = GetFileAttributesW(ip->executable);
if (attrs == INVALID_FILE_ATTRIBUTES) {
winerror(GetLastError(), message, MSGSIZE);
debug(L"locate_pythons_for_key: %ls: %ls",
ip->executable, message);
}
else if (attrs & FILE_ATTRIBUTE_DIRECTORY) {
debug(L"locate_pythons_for_key: '%ls' is a \
directory\n",
ip->executable, attrs);
}
else if (find_existing_python(ip->executable)) {
debug(L"locate_pythons_for_key: %ls: already \
found\n", ip->executable);
}
else {
/* check the executable type. */
ok = GetBinaryTypeW(ip->executable, &attrs);
if (!ok) {
debug(L"Failure getting binary type: %ls\n",
ip->executable);
}
else {
if (attrs == SCS_64BIT_BINARY)
ip->bits = 64;
else if (attrs == SCS_32BIT_BINARY)
ip->bits = 32;
else
ip->bits = 0;
if (ip->bits == 0) {
debug(L"locate_pythons_for_key: %ls: \
invalid binary type: %X\n",
ip->executable, attrs);
}
else {
if (wcschr(ip->executable, L' ') != NULL) {
/* has spaces, so quote */
n = wcslen(ip->executable);
memmove(&ip->executable[1],
ip->executable, n * sizeof(wchar_t));
ip->executable[0] = L'\"';
ip->executable[n + 1] = L'\"';
ip->executable[n + 2] = L'\0';
}
debug(L"locate_pythons_for_key: %ls \
is a %dbit executable\n",
ip->executable, ip->bits);
++num_installed_pythons;
pip = ip++;
if (num_installed_pythons >=
MAX_INSTALLED_PYTHONS)
break;
/* Copy over the attributes for the next */
*ip = *pip;
}
}
}
}
}
}
}
RegCloseKey(core_root);
}
}
static int
compare_pythons(const void * p1, const void * p2)
{
INSTALLED_PYTHON * ip1 = (INSTALLED_PYTHON *) p1;
INSTALLED_PYTHON * ip2 = (INSTALLED_PYTHON *) p2;
/* note reverse sorting on version */
int result = wcscmp(ip2->version, ip1->version);
if (result == 0)
result = ip2->bits - ip1->bits; /* 64 before 32 */
return result;
}
static void
locate_all_pythons()
{
#if defined(_M_X64)
// If we are a 64bit process, first hit the 32bit keys.
debug(L"locating Pythons in 32bit registry\n");
locate_pythons_for_key(HKEY_CURRENT_USER, KEY_READ | KEY_WOW64_32KEY);
locate_pythons_for_key(HKEY_LOCAL_MACHINE, KEY_READ | KEY_WOW64_32KEY);
#else
// If we are a 32bit process on a 64bit Windows, first hit the 64bit keys.
BOOL f64 = FALSE;
if (IsWow64Process(GetCurrentProcess(), &f64) && f64) {
debug(L"locating Pythons in 64bit registry\n");
locate_pythons_for_key(HKEY_CURRENT_USER, KEY_READ | KEY_WOW64_64KEY);
locate_pythons_for_key(HKEY_LOCAL_MACHINE, KEY_READ | KEY_WOW64_64KEY);
}
#endif
// now hit the "native" key for this process bittedness.
debug(L"locating Pythons in native registry\n");
locate_pythons_for_key(HKEY_CURRENT_USER, KEY_READ);
locate_pythons_for_key(HKEY_LOCAL_MACHINE, KEY_READ);
qsort(installed_pythons, num_installed_pythons, sizeof(INSTALLED_PYTHON),
compare_pythons);
}
static INSTALLED_PYTHON *
find_python_by_version(wchar_t const * wanted_ver)
{
INSTALLED_PYTHON * result = NULL;
INSTALLED_PYTHON * ip = installed_pythons;
size_t i, n;
size_t wlen = wcslen(wanted_ver);
int bits = 0;
if (wcsstr(wanted_ver, L"-32"))
bits = 32;
for (i = 0; i < num_installed_pythons; i++, ip++) {
n = wcslen(ip->version);
if (n > wlen)
n = wlen;
if ((wcsncmp(ip->version, wanted_ver, n) == 0) &&
/* bits == 0 => don't care */
((bits == 0) || (ip->bits == bits))) {
result = ip;
break;
}
}
return result;
}
static wchar_t *
find_python_by_venv()
{
static wchar_t venv_python[MAX_PATH];
wchar_t *virtual_env = get_env(L"VIRTUAL_ENV");
DWORD attrs;
/* Check for VIRTUAL_ENV environment variable */
if (virtual_env == NULL || virtual_env[0] == L'\0') {
return NULL;
}
/* Check for a python executable in the venv */
debug(L"Checking for Python executable in virtual env '%ls'\n", virtual_env);
_snwprintf_s(venv_python, MAX_PATH, _TRUNCATE,
L"%ls\\Scripts\\%ls", virtual_env, PYTHON_EXECUTABLE);
attrs = GetFileAttributesW(venv_python);
if (attrs == INVALID_FILE_ATTRIBUTES) {
debug(L"Python executable %ls missing from virtual env\n", venv_python);
return NULL;
}
return venv_python;
}
static wchar_t appdata_ini_path[MAX_PATH];
static wchar_t launcher_ini_path[MAX_PATH];
/*
* Get a value either from the environment or a configuration file.
* The key passed in will either be "python", "python2" or "python3".
*/
static wchar_t *
get_configured_value(wchar_t * key)
{
/*
* Note: this static value is used to return a configured value
* obtained either from the environment or configuration file.
* This should be OK since there wouldn't be any concurrent calls.
*/
static wchar_t configured_value[MSGSIZE];
wchar_t * result = NULL;
wchar_t * found_in = L"environment";
DWORD size;
/* First, search the environment. */
_snwprintf_s(configured_value, MSGSIZE, _TRUNCATE, L"py_%ls", key);
result = get_env(configured_value);
if (result == NULL && appdata_ini_path[0]) {
/* Not in environment: check local configuration. */
size = GetPrivateProfileStringW(L"defaults", key, NULL,
configured_value, MSGSIZE,
appdata_ini_path);
if (size > 0) {
result = configured_value;
found_in = appdata_ini_path;
}
}
if (result == NULL && launcher_ini_path[0]) {
/* Not in environment or local: check global configuration. */
size = GetPrivateProfileStringW(L"defaults", key, NULL,
configured_value, MSGSIZE,
launcher_ini_path);
if (size > 0) {
result = configured_value;
found_in = launcher_ini_path;
}
}
if (result) {
debug(L"found configured value '%ls=%ls' in %ls\n",
key, result, found_in ? found_in : L"(unknown)");
} else {
debug(L"found no configured value for '%ls'\n", key);
}
return result;
}
static INSTALLED_PYTHON *
locate_python(wchar_t * wanted_ver)
{
static wchar_t config_key [] = { L"pythonX" };
static wchar_t * last_char = &config_key[sizeof(config_key) /
sizeof(wchar_t) - 2];
INSTALLED_PYTHON * result = NULL;
size_t n = wcslen(wanted_ver);
wchar_t * configured_value;
if (num_installed_pythons == 0)
locate_all_pythons();
if (n == 1) { /* just major version specified */
*last_char = *wanted_ver;
configured_value = get_configured_value(config_key);
if (configured_value != NULL)
wanted_ver = configured_value;
}
if (*wanted_ver) {
result = find_python_by_version(wanted_ver);
debug(L"search for Python version '%ls' found ", wanted_ver);
if (result) {
debug(L"'%ls'\n", result->executable);
} else {
debug(L"no interpreter\n");
}
}
else {
*last_char = L'\0'; /* look for an overall default */
configured_value = get_configured_value(config_key);
if (configured_value)
result = find_python_by_version(configured_value);
if (result == NULL)
result = find_python_by_version(L"2");
if (result == NULL)
result = find_python_by_version(L"3");
debug(L"search for default Python found ");
if (result) {
debug(L"version %ls at '%ls'\n",
result->version, result->executable);
} else {
debug(L"no interpreter\n");
}
}
return result;
}
#if defined(SCRIPT_WRAPPER)
/*
* Check for a script located alongside the executable
*/
#if defined(_WINDOWS)
#define SCRIPT_SUFFIX L"-script.pyw"
#else
#define SCRIPT_SUFFIX L"-script.py"
#endif
static wchar_t wrapped_script_path[MAX_PATH];
/* Locate the script being wrapped.
*
* This code should store the name of the wrapped script in
* wrapped_script_path, or terminate the program with an error if there is no
* valid wrapped script file.
*/
static void
locate_wrapped_script()
{
wchar_t * p;
size_t plen;
DWORD attrs;
plen = GetModuleFileNameW(NULL, wrapped_script_path, MAX_PATH);
p = wcsrchr(wrapped_script_path, L'.');
if (p == NULL) {
debug(L"GetModuleFileNameW returned value has no extension: %ls\n",
wrapped_script_path);
error(RC_NO_SCRIPT, L"Wrapper name '%ls' is not valid.", wrapped_script_path);
}
wcsncpy_s(p, MAX_PATH - (p - wrapped_script_path) + 1, SCRIPT_SUFFIX, _TRUNCATE);
attrs = GetFileAttributesW(wrapped_script_path);
if (attrs == INVALID_FILE_ATTRIBUTES) {
debug(L"File '%ls' non-existent\n", wrapped_script_path);
error(RC_NO_SCRIPT, L"Script file '%ls' is not present.", wrapped_script_path);
}
debug(L"Using wrapped script file '%ls'\n", wrapped_script_path);
}
#endif
/*
* Process creation code
*/
static BOOL
safe_duplicate_handle(HANDLE in, HANDLE * pout)
{
BOOL ok;
HANDLE process = GetCurrentProcess();
DWORD rc;
*pout = NULL;
ok = DuplicateHandle(process, in, process, pout, 0, TRUE,
DUPLICATE_SAME_ACCESS);
if (!ok) {
rc = GetLastError();
if (rc == ERROR_INVALID_HANDLE) {
debug(L"DuplicateHandle returned ERROR_INVALID_HANDLE\n");
ok = TRUE;
}
else {
debug(L"DuplicateHandle returned %d\n", rc);
}
}
return ok;
}
static BOOL WINAPI
ctrl_c_handler(DWORD code)
{
return TRUE; /* We just ignore all control events. */
}
static void
run_child(wchar_t * cmdline)
{
HANDLE job;
JOBOBJECT_EXTENDED_LIMIT_INFORMATION info;
DWORD rc;
BOOL ok;
STARTUPINFOW si;
PROCESS_INFORMATION pi;
#if defined(_WINDOWS)
// When explorer launches a Windows (GUI) application, it displays
// the "app starting" (the "pointer + hourglass") cursor for a number
// of seconds, or until the app does something UI-ish (eg, creating a
// window, or fetching a message). As this launcher doesn't do this
// directly, that cursor remains even after the child process does these
// things. We avoid that by doing a simple post+get message.
// See http://bugs.python.org/issue17290 and
// https://bitbucket.org/vinay.sajip/pylauncher/issue/20/busy-cursor-for-a-long-time-when-running
MSG msg;
PostMessage(0, 0, 0, 0);
GetMessage(&msg, 0, 0, 0);
#endif
debug(L"run_child: about to run '%ls'\n", cmdline);
job = CreateJobObject(NULL, NULL);
ok = QueryInformationJobObject(job, JobObjectExtendedLimitInformation,
&info, sizeof(info), &rc);
if (!ok || (rc != sizeof(info)) || !job)
error(RC_CREATE_PROCESS, L"Job information querying failed");
info.BasicLimitInformation.LimitFlags |= JOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSE |
JOB_OBJECT_LIMIT_SILENT_BREAKAWAY_OK;
ok = SetInformationJobObject(job, JobObjectExtendedLimitInformation, &info,
sizeof(info));
if (!ok)
error(RC_CREATE_PROCESS, L"Job information setting failed");
memset(&si, 0, sizeof(si));
si.cb = sizeof(si);
ok = safe_duplicate_handle(GetStdHandle(STD_INPUT_HANDLE), &si.hStdInput);
if (!ok)
error(RC_NO_STD_HANDLES, L"stdin duplication failed");
ok = safe_duplicate_handle(GetStdHandle(STD_OUTPUT_HANDLE), &si.hStdOutput);
if (!ok)
error(RC_NO_STD_HANDLES, L"stdout duplication failed");
ok = safe_duplicate_handle(GetStdHandle(STD_ERROR_HANDLE), &si.hStdError);
if (!ok)
error(RC_NO_STD_HANDLES, L"stderr duplication failed");
ok = SetConsoleCtrlHandler(ctrl_c_handler, TRUE);
if (!ok)
error(RC_CREATE_PROCESS, L"control handler setting failed");
si.dwFlags = STARTF_USESTDHANDLES;
ok = CreateProcessW(NULL, cmdline, NULL, NULL, TRUE,
0, NULL, NULL, &si, &pi);
if (!ok)
error(RC_CREATE_PROCESS, L"Unable to create process using '%ls'", cmdline);
AssignProcessToJobObject(job, pi.hProcess);
CloseHandle(pi.hThread);
WaitForSingleObjectEx(pi.hProcess, INFINITE, FALSE);
ok = GetExitCodeProcess(pi.hProcess, &rc);
if (!ok)
error(RC_CREATE_PROCESS, L"Failed to get exit code of process");
debug(L"child process exit code: %d\n", rc);
exit(rc);
}
static void
invoke_child(wchar_t * executable, wchar_t * suffix, wchar_t * cmdline)
{
wchar_t * child_command;
size_t child_command_size;
BOOL no_suffix = (suffix == NULL) || (*suffix == L'\0');
BOOL no_cmdline = (*cmdline == L'\0');
if (no_suffix && no_cmdline)
run_child(executable);
else {
if (no_suffix) {
/* add 2 for space separator + terminating NUL. */
child_command_size = wcslen(executable) + wcslen(cmdline) + 2;
}
else {
/* add 3 for 2 space separators + terminating NUL. */
child_command_size = wcslen(executable) + wcslen(suffix) +
wcslen(cmdline) + 3;
}
child_command = calloc(child_command_size, sizeof(wchar_t));
if (child_command == NULL)
error(RC_CREATE_PROCESS, L"unable to allocate %d bytes for child command.",
child_command_size);
if (no_suffix)
_snwprintf_s(child_command, child_command_size,
child_command_size - 1, L"%ls %ls",
executable, cmdline);
else
_snwprintf_s(child_command, child_command_size,
child_command_size - 1, L"%ls %ls %ls",
executable, suffix, cmdline);
run_child(child_command);
free(child_command);
}
}
typedef struct {
wchar_t *shebang;
BOOL search;
} SHEBANG;
static SHEBANG builtin_virtual_paths [] = {
{ L"/usr/bin/env python", TRUE },
{ L"/usr/bin/python", FALSE },
{ L"/usr/local/bin/python", FALSE },
{ L"python", FALSE },
{ NULL, FALSE },
};
/* For now, a static array of commands. */
#define MAX_COMMANDS 100
typedef struct {
wchar_t key[MAX_PATH];
wchar_t value[MSGSIZE];
} COMMAND;
static COMMAND commands[MAX_COMMANDS];
static int num_commands = 0;
#if defined(SKIP_PREFIX)
static wchar_t * builtin_prefixes [] = {
/* These must be in an order that the longest matches should be found,
* i.e. if the prefix is "/usr/bin/env ", it should match that entry
* *before* matching "/usr/bin/".
*/
L"/usr/bin/env ",
L"/usr/bin/",
L"/usr/local/bin/",
NULL
};
static wchar_t * skip_prefix(wchar_t * name)
{
wchar_t ** pp = builtin_prefixes;
wchar_t * result = name;
wchar_t * p;
size_t n;
for (; p = *pp; pp++) {
n = wcslen(p);
if (_wcsnicmp(p, name, n) == 0) {
result += n; /* skip the prefix */
if (p[n - 1] == L' ') /* No empty strings in table, so n > 1 */
result = skip_whitespace(result);
break;
}
}
return result;
}
#endif
#if defined(SEARCH_PATH)
static COMMAND path_command;
static COMMAND * find_on_path(wchar_t * name)
{
wchar_t * pathext;
size_t varsize;
wchar_t * context = NULL;
wchar_t * extension;
COMMAND * result = NULL;
DWORD len;
errno_t rc;
wcscpy_s(path_command.key, MAX_PATH, name);
if (wcschr(name, L'.') != NULL) {
/* assume it has an extension. */
len = SearchPathW(NULL, name, NULL, MSGSIZE, path_command.value, NULL);
if (len) {
result = &path_command;
}
}
else {
/* No extension - search using registered extensions. */
rc = _wdupenv_s(&pathext, &varsize, L"PATHEXT");
if (rc == 0) {
extension = wcstok_s(pathext, L";", &context);
while (extension) {
len = SearchPathW(NULL, name, extension, MSGSIZE, path_command.value, NULL);
if (len) {
result = &path_command;
break;
}
extension = wcstok_s(NULL, L";", &context);
}
free(pathext);
}
}
return result;
}
#endif
static COMMAND * find_command(wchar_t * name)
{
COMMAND * result = NULL;
COMMAND * cp = commands;
int i;
for (i = 0; i < num_commands; i++, cp++) {
if (_wcsicmp(cp->key, name) == 0) {
result = cp;
break;
}
}
#if defined(SEARCH_PATH)
if (result == NULL)
result = find_on_path(name);
#endif
return result;
}
static void
update_command(COMMAND * cp, wchar_t * name, wchar_t * cmdline)
{
wcsncpy_s(cp->key, MAX_PATH, name, _TRUNCATE);
wcsncpy_s(cp->value, MSGSIZE, cmdline, _TRUNCATE);
}
static void
add_command(wchar_t * name, wchar_t * cmdline)
{
if (num_commands >= MAX_COMMANDS) {
debug(L"can't add %ls = '%ls': no room\n", name, cmdline);
}
else {
COMMAND * cp = &commands[num_commands++];
update_command(cp, name, cmdline);
}
}
static void
read_config_file(wchar_t * config_path)
{
wchar_t keynames[MSGSIZE];
wchar_t value[MSGSIZE];
DWORD read;
wchar_t * key;
COMMAND * cp;
wchar_t * cmdp;
read = GetPrivateProfileStringW(L"commands", NULL, NULL, keynames, MSGSIZE,
config_path);
if (read == MSGSIZE - 1) {
debug(L"read_commands: %ls: not enough space for names\n", config_path);
}
key = keynames;
while (*key) {
read = GetPrivateProfileStringW(L"commands", key, NULL, value, MSGSIZE,
config_path);
if (read == MSGSIZE - 1) {
debug(L"read_commands: %ls: not enough space for %ls\n",
config_path, key);
}
cmdp = skip_whitespace(value);
if (*cmdp) {
cp = find_command(key);
if (cp == NULL)
add_command(key, value);
else
update_command(cp, key, value);
}
key += wcslen(key) + 1;
}
}
static void read_commands()
{
if (launcher_ini_path[0])
read_config_file(launcher_ini_path);
if (appdata_ini_path[0])
read_config_file(appdata_ini_path);
}
static BOOL
parse_shebang(wchar_t * shebang_line, int nchars, wchar_t ** command,
wchar_t ** suffix, BOOL *search)
{
BOOL rc = FALSE;
SHEBANG * vpp;
size_t plen;
wchar_t * p;
wchar_t zapped;
wchar_t * endp = shebang_line + nchars - 1;
COMMAND * cp;
wchar_t * skipped;
*command = NULL; /* failure return */
*suffix = NULL;
*search = FALSE;
if ((*shebang_line++ == L'#') && (*shebang_line++ == L'!')) {
shebang_line = skip_whitespace(shebang_line);
if (*shebang_line) {
*command = shebang_line;
for (vpp = builtin_virtual_paths; vpp->shebang; ++vpp) {
plen = wcslen(vpp->shebang);
if (wcsncmp(shebang_line, vpp->shebang, plen) == 0) {
rc = TRUE;
*search = vpp->search;
/* We can do this because all builtin commands contain
* "python".
*/
*command = wcsstr(shebang_line, L"python");
break;
}
}
if (vpp->shebang == NULL) {
/*
* Not found in builtins - look in customized commands.
*
* We can't permanently modify the shebang line in case
* it's not a customized command, but we can temporarily
* stick a NUL after the command while searching for it,
* then put back the char we zapped.
*/
#if defined(SKIP_PREFIX)
skipped = skip_prefix(shebang_line);
#else
skipped = shebang_line;
#endif
p = wcspbrk(skipped, L" \t\r\n");
if (p != NULL) {
zapped = *p;
*p = L'\0';
}
cp = find_command(skipped);
if (p != NULL)
*p = zapped;
if (cp != NULL) {
*command = cp->value;
if (p != NULL)
*suffix = skip_whitespace(p);
}
}
/* remove trailing whitespace */
while ((endp > shebang_line) && isspace(*endp))
--endp;
if (endp > shebang_line)
endp[1] = L'\0';
}
}
return rc;
}
/* #define CP_UTF8 65001 defined in winnls.h */
#define CP_UTF16LE 1200
#define CP_UTF16BE 1201
#define CP_UTF32LE 12000
#define CP_UTF32BE 12001
typedef struct {
int length;
char sequence[4];
UINT code_page;
} BOM;
/*
* Strictly, we don't need to handle UTF-16 and UTF-32, since Python itself
* doesn't. Never mind, one day it might - there's no harm leaving it in.
*/
static BOM BOMs[] = {
{ 3, { 0xEF, 0xBB, 0xBF }, CP_UTF8 }, /* UTF-8 - keep first */
/* Test UTF-32LE before UTF-16LE since UTF-16LE BOM is a prefix
* of UTF-32LE BOM. */
{ 4, { 0xFF, 0xFE, 0x00, 0x00 }, CP_UTF32LE }, /* UTF-32LE */
{ 4, { 0x00, 0x00, 0xFE, 0xFF }, CP_UTF32BE }, /* UTF-32BE */
{ 2, { 0xFF, 0xFE }, CP_UTF16LE }, /* UTF-16LE */
{ 2, { 0xFE, 0xFF }, CP_UTF16BE }, /* UTF-16BE */
{ 0 } /* sentinel */
};
static BOM *
find_BOM(char * buffer)
{
/*
* Look for a BOM in the input and return a pointer to the
* corresponding structure, or NULL if not found.
*/
BOM * result = NULL;
BOM *bom;
for (bom = BOMs; bom->length; bom++) {
if (strncmp(bom->sequence, buffer, bom->length) == 0) {
result = bom;
break;
}
}
return result;
}
static char *
find_terminator(char * buffer, int len, BOM *bom)
{
char * result = NULL;
char * end = buffer + len;
char * p;
char c;
int cp;
for (p = buffer; p < end; p++) {
c = *p;
if (c == '\r') {
result = p;
break;
}
if (c == '\n') {
result = p;
break;
}
}
if (result != NULL) {
cp = bom->code_page;
/* adjustments to include all bytes of the char */
/* no adjustment needed for UTF-8 or big endian */
if (cp == CP_UTF16LE)
++result;
else if (cp == CP_UTF32LE)
result += 3;
++result; /* point just past terminator */
}
return result;
}
static BOOL
validate_version(wchar_t * p)
{
BOOL result = TRUE;
if (!isdigit(*p)) /* expect major version */
result = FALSE;
else if (*++p) { /* more to do */
if (*p != L'.') /* major/minor separator */
result = FALSE;
else {
++p;
if (!isdigit(*p)) /* expect minor version */
result = FALSE;
else {
++p;
if (*p) { /* more to do */
if (*p != L'-')
result = FALSE;
else {
++p;
if ((*p != '3') && (*++p != '2') && !*++p)
result = FALSE;
}
}
}
}
}
return result;
}
typedef struct {
unsigned short min;
unsigned short max;
wchar_t version[MAX_VERSION_SIZE];
} PYC_MAGIC;
static PYC_MAGIC magic_values[] = {
{ 0xc687, 0xc687, L"2.0" },
{ 0xeb2a, 0xeb2a, L"2.1" },
{ 0xed2d, 0xed2d, L"2.2" },
{ 0xf23b, 0xf245, L"2.3" },
{ 0xf259, 0xf26d, L"2.4" },
{ 0xf277, 0xf2b3, L"2.5" },
{ 0xf2c7, 0xf2d1, L"2.6" },
{ 0xf2db, 0xf303, L"2.7" },
{ 0x0bb8, 0x0c3b, L"3.0" },
{ 0x0c45, 0x0c4f, L"3.1" },
{ 0x0c58, 0x0c6c, L"3.2" },
{ 0x0c76, 0x0c9e, L"3.3" },
{ 0x0cb2, 0x0cee, L"3.4" },
{ 0x0cf8, 0x0d16, L"3.5" },
{ 0x0d20, 0x0d20, L"3.6" },
{ 0 }
};
static INSTALLED_PYTHON *
find_by_magic(unsigned short magic)
{
INSTALLED_PYTHON * result = NULL;
PYC_MAGIC * mp;
for (mp = magic_values; mp->min; mp++) {
if ((magic >= mp->min) && (magic <= mp->max)) {
result = locate_python(mp->version);
if (result != NULL)
break;
}
}
return result;
}
static void
maybe_handle_shebang(wchar_t ** argv, wchar_t * cmdline)
{
/*
* Look for a shebang line in the first argument. If found
* and we spawn a child process, this never returns. If it
* does return then we process the args "normally".
*
* argv[0] might be a filename with a shebang.
*/
FILE * fp;
errno_t rc = _wfopen_s(&fp, *argv, L"rb");
char buffer[BUFSIZE];
wchar_t shebang_line[BUFSIZE + 1];
size_t read;
char *p;
char * start;
char * shebang_alias = (char *) shebang_line;
BOM* bom;
int i, j, nchars = 0;
int header_len;
BOOL is_virt;
BOOL search;
wchar_t * command;
wchar_t * suffix;
COMMAND *cmd = NULL;
INSTALLED_PYTHON * ip;
if (rc == 0) {
read = fread(buffer, sizeof(char), BUFSIZE, fp);
debug(L"maybe_handle_shebang: read %d bytes\n", read);
fclose(fp);
if ((read >= 4) && (buffer[3] == '\n') && (buffer[2] == '\r')) {
ip = find_by_magic((((unsigned char)buffer[1]) << 8 |
(unsigned char)buffer[0]) & 0xFFFF);
if (ip != NULL) {
debug(L"script file is compiled against Python %ls\n",
ip->version);
invoke_child(ip->executable, NULL, cmdline);
}
}
/* Look for BOM */
bom = find_BOM(buffer);
if (bom == NULL) {
start = buffer;
debug(L"maybe_handle_shebang: BOM not found, using UTF-8\n");
bom = BOMs; /* points to UTF-8 entry - the default */
}
else {
debug(L"maybe_handle_shebang: BOM found, code page %d\n",
bom->code_page);
start = &buffer[bom->length];
}
p = find_terminator(start, BUFSIZE, bom);
/*
* If no CR or LF was found in the heading,
* we assume it's not a shebang file.
*/
if (p == NULL) {
debug(L"maybe_handle_shebang: No line terminator found\n");
}
else {
/*
* Found line terminator - parse the shebang.
*
* Strictly, we don't need to handle UTF-16 anf UTF-32,
* since Python itself doesn't.
* Never mind, one day it might.
*/
header_len = (int) (p - start);
switch(bom->code_page) {
case CP_UTF8:
nchars = MultiByteToWideChar(bom->code_page,
0,
start, header_len, shebang_line,
BUFSIZE);
break;
case CP_UTF16BE:
if (header_len % 2 != 0) {
debug(L"maybe_handle_shebang: UTF-16BE, but an odd number \
of bytes: %d\n", header_len);
/* nchars = 0; Not needed - initialised to 0. */
}
else {
for (i = header_len; i > 0; i -= 2) {
shebang_alias[i - 1] = start[i - 2];
shebang_alias[i - 2] = start[i - 1];
}
nchars = header_len / sizeof(wchar_t);
}
break;
case CP_UTF16LE:
if ((header_len % 2) != 0) {
debug(L"UTF-16LE, but an odd number of bytes: %d\n",
header_len);
/* nchars = 0; Not needed - initialised to 0. */
}
else {
/* no actual conversion needed. */
memcpy(shebang_line, start, header_len);
nchars = header_len / sizeof(wchar_t);
}
break;
case CP_UTF32BE:
if (header_len % 4 != 0) {
debug(L"UTF-32BE, but not divisible by 4: %d\n",
header_len);
/* nchars = 0; Not needed - initialised to 0. */
}
else {
for (i = header_len, j = header_len / 2; i > 0; i -= 4,
j -= 2) {
shebang_alias[j - 1] = start[i - 2];
shebang_alias[j - 2] = start[i - 1];
}
nchars = header_len / sizeof(wchar_t);
}
break;
case CP_UTF32LE:
if (header_len % 4 != 0) {
debug(L"UTF-32LE, but not divisible by 4: %d\n",
header_len);
/* nchars = 0; Not needed - initialised to 0. */
}
else {
for (i = header_len, j = header_len / 2; i > 0; i -= 4,
j -= 2) {
shebang_alias[j - 1] = start[i - 3];
shebang_alias[j - 2] = start[i - 4];
}
nchars = header_len / sizeof(wchar_t);
}
break;
}
if (nchars > 0) {
shebang_line[--nchars] = L'\0';
is_virt = parse_shebang(shebang_line, nchars, &command,
&suffix, &search);
if (command != NULL) {
debug(L"parse_shebang: found command: %ls\n", command);
if (!is_virt) {
invoke_child(command, suffix, cmdline);
}
else {
suffix = wcschr(command, L' ');
if (suffix != NULL) {
*suffix++ = L'\0';
suffix = skip_whitespace(suffix);
}
if (wcsncmp(command, L"python", 6))
error(RC_BAD_VIRTUAL_PATH, L"Unknown virtual \
path '%ls'", command);
command += 6; /* skip past "python" */
if (search && ((*command == L'\0') || isspace(*command))) {
/* Command is eligible for path search, and there
* is no version specification.
*/
debug(L"searching PATH for python executable\n");
cmd = find_on_path(PYTHON_EXECUTABLE);
debug(L"Python on path: %ls\n", cmd ? cmd->value : L"<not found>");
if (cmd) {
debug(L"located python on PATH: %ls\n", cmd->value);
invoke_child(cmd->value, suffix, cmdline);
/* Exit here, as we have found the command */
return;
}
/* FALL THROUGH: No python found on PATH, so fall
* back to locating the correct installed python.
*/
}
if (*command && !validate_version(command))
error(RC_BAD_VIRTUAL_PATH, L"Invalid version \
specification: '%ls'.\nIn the first line of the script, 'python' needs to be \
followed by a valid version specifier.\nPlease check the documentation.",
command);
/* TODO could call validate_version(command) */
ip = locate_python(command);
if (ip == NULL) {
error(RC_NO_PYTHON, L"Requested Python version \
(%ls) is not installed", command);
}
else {
invoke_child(ip->executable, suffix, cmdline);
}
}
}
}
}
}
}
static wchar_t *
skip_me(wchar_t * cmdline)
{
BOOL quoted;
wchar_t c;
wchar_t * result = cmdline;
quoted = cmdline[0] == L'\"';
if (!quoted)
c = L' ';
else {
c = L'\"';
++result;
}
result = wcschr(result, c);
if (result == NULL) /* when, for example, just exe name on command line */
result = L"";
else {
++result; /* skip past space or closing quote */
result = skip_whitespace(result);
}
return result;
}
static DWORD version_high = 0;
static DWORD version_low = 0;
static void
get_version_info(wchar_t * version_text, size_t size)
{
WORD maj, min, rel, bld;
if (!version_high && !version_low)
wcsncpy_s(version_text, size, L"0.1", _TRUNCATE); /* fallback */
else {
maj = HIWORD(version_high);
min = LOWORD(version_high);
rel = HIWORD(version_low);
bld = LOWORD(version_low);
_snwprintf_s(version_text, size, _TRUNCATE, L"%d.%d.%d.%d", maj,
min, rel, bld);
}
}
static int
process(int argc, wchar_t ** argv)
{
wchar_t * wp;
wchar_t * command;
wchar_t * executable;
wchar_t * p;
int rc = 0;
size_t plen;
INSTALLED_PYTHON * ip;
BOOL valid;
DWORD size, attrs;
HRESULT hr;
wchar_t message[MSGSIZE];
wchar_t version_text [MAX_PATH];
void * version_data;
VS_FIXEDFILEINFO * file_info;
UINT block_size;
int index;
#if defined(SCRIPT_WRAPPER)
int newlen;
wchar_t * newcommand;
wchar_t * av[2];
#endif
setvbuf(stderr, (char *)NULL, _IONBF, 0);
wp = get_env(L"PYLAUNCH_DEBUG");
if ((wp != NULL) && (*wp != L'\0'))
log_fp = stderr;
#if defined(_M_X64)
debug(L"launcher build: 64bit\n");
#else
debug(L"launcher build: 32bit\n");
#endif
#if defined(_WINDOWS)
debug(L"launcher executable: Windows\n");
#else
debug(L"launcher executable: Console\n");
#endif
/* Get the local appdata folder (non-roaming) */
hr = SHGetFolderPathW(NULL, CSIDL_LOCAL_APPDATA,
NULL, 0, appdata_ini_path);
if (hr != S_OK) {
debug(L"SHGetFolderPath failed: %X\n", hr);
appdata_ini_path[0] = L'\0';
}
else {
plen = wcslen(appdata_ini_path);
p = &appdata_ini_path[plen];
wcsncpy_s(p, MAX_PATH - plen, L"\\py.ini", _TRUNCATE);
attrs = GetFileAttributesW(appdata_ini_path);
if (attrs == INVALID_FILE_ATTRIBUTES) {
debug(L"File '%ls' non-existent\n", appdata_ini_path);
appdata_ini_path[0] = L'\0';
} else {
debug(L"Using local configuration file '%ls'\n", appdata_ini_path);
}
}
plen = GetModuleFileNameW(NULL, launcher_ini_path, MAX_PATH);
size = GetFileVersionInfoSizeW(launcher_ini_path, &size);
if (size == 0) {
winerror(GetLastError(), message, MSGSIZE);
debug(L"GetFileVersionInfoSize failed: %ls\n", message);
}
else {
version_data = malloc(size);
if (version_data) {
valid = GetFileVersionInfoW(launcher_ini_path, 0, size,
version_data);
if (!valid)
debug(L"GetFileVersionInfo failed: %X\n", GetLastError());
else {
valid = VerQueryValueW(version_data, L"\\",
(LPVOID *) &file_info, &block_size);
if (!valid)
debug(L"VerQueryValue failed: %X\n", GetLastError());
else {
version_high = file_info->dwFileVersionMS;
version_low = file_info->dwFileVersionLS;
}
}
free(version_data);
}
}
p = wcsrchr(launcher_ini_path, L'\\');
if (p == NULL) {
debug(L"GetModuleFileNameW returned value has no backslash: %ls\n",
launcher_ini_path);
launcher_ini_path[0] = L'\0';
}
else {
wcsncpy_s(p, MAX_PATH - (p - launcher_ini_path), L"\\py.ini",
_TRUNCATE);
attrs = GetFileAttributesW(launcher_ini_path);
if (attrs == INVALID_FILE_ATTRIBUTES) {
debug(L"File '%ls' non-existent\n", launcher_ini_path);
launcher_ini_path[0] = L'\0';
} else {
debug(L"Using global configuration file '%ls'\n", launcher_ini_path);
}
}
command = skip_me(GetCommandLineW());
debug(L"Called with command line: %ls\n", command);
#if defined(SCRIPT_WRAPPER)
/* The launcher is being used in "script wrapper" mode.
* There should therefore be a Python script named <exename>-script.py in
* the same directory as the launcher executable.
* Put the script name into argv as the first (script name) argument.
*/
/* Get the wrapped script name - if the script is not present, this will
* terminate the program with an error.
*/
locate_wrapped_script();
/* Add the wrapped script to the start of command */
newlen = wcslen(wrapped_script_path) + wcslen(command) + 2; /* ' ' + 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);
wcscat_s(newcommand, newlen, L" ");
wcscat_s(newcommand, newlen, command);
debug(L"Running wrapped script with command line '%ls'\n", newcommand);
read_commands();
av[0] = wrapped_script_path;
av[1] = NULL;
maybe_handle_shebang(av, newcommand);
/* Returns if no shebang line - pass to default processing */
command = newcommand;
valid = FALSE;
}
#else
if (argc <= 1) {
valid = FALSE;
p = NULL;
}
else {
p = argv[1];
plen = wcslen(p);
valid = (*p == L'-') && validate_version(&p[1]);
if (valid) {
ip = locate_python(&p[1]);
if (ip == NULL)
error(RC_NO_PYTHON, L"Requested Python version (%ls) not \
installed", &p[1]);
executable = ip->executable;
command += wcslen(p);
command = skip_whitespace(command);
}
else {
for (index = 1; index < argc; ++index) {
if (*argv[index] != L'-')
break;
}
if (index < argc) {
read_commands();
maybe_handle_shebang(&argv[index], command);
}
}
}
#endif
if (!valid) {
/* Look for an active virtualenv */
executable = find_python_by_venv();
/* If we didn't find one, look for the default Python */
if (executable == NULL) {
ip = locate_python(L"");
if (ip == NULL)
error(RC_NO_PYTHON, L"Can't find a default Python.");
executable = ip->executable;
}
if ((argc == 2) && (!_wcsicmp(p, L"-h") || !_wcsicmp(p, L"--help"))) {
#if defined(_M_X64)
BOOL canDo64bit = TRUE;
#else
// If we are a 32bit process on a 64bit Windows, first hit the 64bit keys.
BOOL canDo64bit = FALSE;
IsWow64Process(GetCurrentProcess(), &canDo64bit);
#endif
get_version_info(version_text, MAX_PATH);
fwprintf(stdout, L"\
Python Launcher for Windows Version %ls\n\n", version_text);
fwprintf(stdout, L"\
usage: %ls [ launcher-arguments ] [ python-arguments ] script [ script-arguments ]\n\n", argv[0]);
fputws(L"\
Launcher arguments:\n\n\
-2 : Launch the latest Python 2.x version\n\
-3 : Launch the latest Python 3.x version\n\
-X.Y : Launch the specified Python version\n", stdout);
if (canDo64bit) {
fputws(L"\
-X.Y-32: Launch the specified 32bit Python version", stdout);
}
fputws(L"\n\nThe following help text is from Python:\n\n", stdout);
fflush(stdout);
}
}
invoke_child(executable, NULL, command);
return rc;
}
#if defined(_WINDOWS)
int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
LPWSTR lpstrCmd, int nShow)
{
return process(__argc, __wargv);
}
#else
int cdecl wmain(int argc, wchar_t ** argv)
{
return process(argc, argv);
}
#endif