path: root/Python/modsupport.c

/* Module support implementation */

#include "Python.h"

#define FLAG_SIZE_T 1
typedef double va_double;

static PyObject *va_build_value(const char *, va_list, int);

/* Package context -- the full module name for package imports */
char *_Py_PackageContext = NULL;

/* Py_InitModule4() parameters:
   - name is the module name
   - methods is the list of top-level functions
   - doc is the documentation string
   - passthrough is passed as self to functions defined in the module
   - api_version is the value of PYTHON_API_VERSION at the time the
     module was compiled

   Return value is a borrowed reference to the module object; or NULL
   if an error occurred (in Python 1.4 and before, errors were fatal).
   Errors may still leak memory.
*/

static char api_version_warning[] =
"Python C API version mismatch for module %.100s:\
 This Python has API version %d, module %.100s has version %d.";

PyObject *
Py_InitModule4(const char *name, PyMethodDef *methods, const char *doc,
	       PyObject *passthrough, int module_api_version)
{
	PyObject *m, *d, *v, *n;
	PyMethodDef *ml;
	if (!Py_IsInitialized())
	    Py_FatalError("Interpreter not initialized (version mismatch?)");
	if (module_api_version != PYTHON_API_VERSION) {
		char message[512];
		PyOS_snprintf(message, sizeof(message), 
			      api_version_warning, name, 
			      PYTHON_API_VERSION, name, 
			      module_api_version);
		if (PyErr_Warn(PyExc_RuntimeWarning, message)) 
			return NULL;
	}
	/* Make sure name is fully qualified.

	   This is a bit of a hack: when the shared library is loaded,
	   the module name is "package.module", but the module calls
	   Py_InitModule*() with just "module" for the name.  The shared
	   library loader squirrels away the true name of the module in
	   _Py_PackageContext, and Py_InitModule*() will substitute this
	   (if the name actually matches).
	*/
	if (_Py_PackageContext != NULL) {
		char *p = strrchr(_Py_PackageContext, '.');
		if (p != NULL && strcmp(name, p+1) == 0) {
			name = _Py_PackageContext;
			_Py_PackageContext = NULL;
		}
	}
	if ((m = PyImport_AddModule(name)) == NULL)
		return NULL;
	d = PyModule_GetDict(m);
	if (methods != NULL) {
		n = PyString_FromString(name);
		if (n == NULL)
			return NULL;
		for (ml = methods; ml->ml_name != NULL; ml++) {
			if ((ml->ml_flags & METH_CLASS) ||
			    (ml->ml_flags & METH_STATIC)) {
				PyErr_SetString(PyExc_ValueError,
						"module functions cannot set"
						" METH_CLASS or METH_STATIC");
				Py_DECREF(n);
				return NULL;
			}
			v = PyCFunction_NewEx(ml, passthrough, n);
			if (v == NULL) {
				Py_DECREF(n);
				return NULL;
			}
			if (PyDict_SetItemString(d, ml->ml_name, v) != 0) {
				Py_DECREF(v);
				Py_DECREF(n);
				return NULL;
			}
			Py_DECREF(v);
		}
		Py_DECREF(n);
	}
	if (doc != NULL) {
		v = PyString_FromString(doc);
		if (v == NULL || PyDict_SetItemString(d, "__doc__", v) != 0) {
			Py_XDECREF(v);
			return NULL;
		}
		Py_DECREF(v);
	}
	return m;
}


/* Helper for mkvalue() to scan the length of a format */

static int
countformat(const char *format, int endchar)
{
	int count = 0;
	int level = 0;
	while (level > 0 || *format != endchar) {
		switch (*format) {
		case '\0':
			/* Premature end */
			PyErr_SetString(PyExc_SystemError,
					"unmatched paren in format");
			return -1;
		case '(':
		case '[':
		case '{':
			if (level == 0)
				count++;
			level++;
			break;
		case ')':
		case ']':
		case '}':
			level--;
			break;
		case '#':
		case '&':
		case ',':
		case ':':
		case ' ':
		case '\t':
			break;
		default:
			if (level == 0)
				count++;
		}
		format++;
	}
	return count;
}


/* Generic function to create a value -- the inverse of getargs() */
/* After an original idea and first implementation by Steven Miale */

static PyObject *do_mktuple(const char**, va_list *, int, int, int);
static PyObject *do_mklist(const char**, va_list *, int, int, int);
static PyObject *do_mkdict(const char**, va_list *, int, int, int);
static PyObject *do_mkvalue(const char**, va_list *, int);


static PyObject *
do_mkdict(const char **p_format, va_list *p_va, int endchar, int n, int flags)
{
	PyObject *d;
	int i;
	int itemfailed = 0;
	if (n < 0)
		return NULL;
	if ((d = PyDict_New()) == NULL)
		return NULL;
	/* Note that we can't bail immediately on error as this will leak
	   refcounts on any 'N' arguments. */
	for (i = 0; i < n; i+= 2) {
		PyObject *k, *v;
		int err;
		k = do_mkvalue(p_format, p_va, flags);
		if (k == NULL) {
			itemfailed = 1;
			Py_INCREF(Py_None);
			k = Py_None;
		}
		v = do_mkvalue(p_format, p_va, flags);
		if (v == NULL) {
			itemfailed = 1;
			Py_INCREF(Py_None);
			v = Py_None;
		}
		err = PyDict_SetItem(d, k, v);
		Py_DECREF(k);
		Py_DECREF(v);
		if (err < 0 || itemfailed) {
			Py_DECREF(d);
			return NULL;
		}
	}
	if (d != NULL && **p_format != endchar) {
		Py_DECREF(d);
		d = NULL;
		PyErr_SetString(PyExc_SystemError,
				"Unmatched paren in format");
	}
	else if (endchar)
		++*p_format;
	return d;
}

static PyObject *
do_mklist(const char **p_format, va_list *p_va, int endchar, int n, int flags)
{
	PyObject *v;
	int i;
	int itemfailed = 0;
	if (n < 0)
		return NULL;
	v = PyList_New(n);
	if (v == NULL)
		return NULL;
	/* Note that we can't bail immediately on error as this will leak
	   refcounts on any 'N' arguments. */
	for (i = 0; i < n; i++) {
		PyObject *w = do_mkvalue(p_format, p_va, flags);
		if (w == NULL) {
			itemfailed = 1;
			Py_INCREF(Py_None);
			w = Py_None;
		}
		PyList_SET_ITEM(v, i, w);
	}

	if (itemfailed) {
		/* do_mkvalue() should have already set an error */
		Py_DECREF(v);
		return NULL;
	}
	if (**p_format != endchar) {
		Py_DECREF(v);
		PyErr_SetString(PyExc_SystemError,
				"Unmatched paren in format");
		return NULL;
	}
	if (endchar)
		++*p_format;
	return v;
}

#ifdef Py_USING_UNICODE
static int
_ustrlen(Py_UNICODE *u)
{
	int i = 0;
	Py_UNICODE *v = u;
	while (*v != 0) { i++; v++; } 
	return i;
}
#endif

static PyObject *
do_mktuple(const char **p_format, va_list *p_va, int endchar, int n, int flags)
{
	PyObject *v;
	int i;
	int itemfailed = 0;
	if (n < 0)
		return NULL;
	if ((v = PyTuple_New(n)) == NULL)
		return NULL;
	/* Note that we can't bail immediately on error as this will leak
	   refcounts on any 'N' arguments. */
	for (i = 0; i < n; i++) {
		PyObject *w = do_mkvalue(p_format, p_va, flags);
		if (w == NULL) {
			itemfailed = 1;
			Py_INCREF(Py_None);
			w = Py_None;2'>1442