Initial revision

Python/import.c

@@ -0,0 +1,252 @@
+/* Module definition and import implementation */
+
+#include <stdio.h>
+#include "string.h"
+
+#include "PROTO.h"
+#include "object.h"
+#include "stringobject.h"
+#include "listobject.h"
+#include "dictobject.h"
+#include "moduleobject.h"
+#include "node.h"
+#include "context.h"
+#include "token.h"
+#include "graminit.h"
+#include "run.h"
+#include "support.h"
+#include "import.h"
+#include "errcode.h"
+#include "sysmodule.h"
+
+/* Define pathname separator and delimiter in $PYTHONPATH */
+
+#ifdef THINK_C
+#define SEP ':'
+#define DELIM ' '
+#endif
+
+#ifndef SEP
+#define SEP '/'
+#endif
+
+#ifndef DELIM
+#define DELIM ':'
+#endif
+
+void
+initimport()
+{
+	object *v;
+	if ((v = newdictobject()) == NULL)
+		fatal("no mem for module table");
+	if (sysset("modules", v) != 0)
+		fatal("can't assign sys.modules");
+}
+
+object *
+new_module(name)
+	char *name;
+{
+	object *m;
+	object *mtab;
+	mtab = sysget("modules");
+	if (mtab == NULL || !is_dictobject(mtab)) {
+		errno = EBADF;
+		return NULL;
+	}
+	m = newmoduleobject(name);
+	if (m == NULL)
+		return NULL;
+	if (dictinsert(mtab, name, m) != 0) {
+		DECREF(m);
+		return NULL;
+	}
+	return m;
+}
+
+void
+define_module(ctx, name)
+	context *ctx;
+	char *name;
+{
+	object *m, *d;
+	m = new_module(name);
+	if (m == NULL) {
+		puterrno(ctx);
+		return;
+	}
+	d = getmoduledict(m);
+	INCREF(d);
+	DECREF(ctx->ctx_locals);
+	ctx->ctx_locals = d;
+	INCREF(d);
+	DECREF(ctx->ctx_globals);
+	ctx->ctx_globals = d;
+	DECREF(m);
+}
+
+object *
+parsepath(path, delim)
+	char *path;
+	int delim;
+{
+	int i, n;
+	char *p;
+	object *v, *w;
+	
+	n = 1;
+	p = path;
+	while ((p = strchr(p, delim)) != NULL) {
+		n++;
+		p++;
+	}
+	v = newlistobject(n);
+	if (v == NULL)
+		return NULL;
+	for (i = 0; ; i++) {
+		p = strchr(path, delim);
+		if (p == NULL)
+			p = strchr(path, '\0'); /* End of string */
+		w = newsizedstringobject(path, (int) (p - path));
+		if (w == NULL) {
+			DECREF(v);
+			return NULL;
+		}
+		setlistitem(v, i, w);
+		if (*p == '\0')
+			break;
+		path = p+1;
+	}
+	return v;
+}
+
+void
+setpythonpath(path)
+	char *path;
+{
+	object *v;
+	if ((v = parsepath(path, DELIM)) != NULL) {
+		if (sysset("path", v) != 0)
+			fatal("can't assign sys.path");
+		DECREF(v);
+	}
+}
+
+static FILE *
+open_module(name, suffix)
+	char *name;
+	char *suffix;
+{
+	object *path;
+	char namebuf[256];
+	FILE *fp;
+	
+	path = sysget("path");
+	if (path == NULL || !is_listobject(path)) {
+		strcpy(namebuf, name);
+		strcat(namebuf, suffix);
+		fp = fopen(namebuf, "r");
+	}
+	else {
+		int npath = getlistsize(path);
+		int i;
+		fp = NULL;
+		for (i = 0; i < npath; i++) {
+			object *v = getlistitem(path, i);
+			int len;
+			if (!is_stringobject(v))
+				continue;
+			strcpy(namebuf, getstringvalue(v));
+			len = getstringsize(v);
+			if (len > 0 && namebuf[len-1] != SEP)
+				namebuf[len++] = SEP;
+			strcpy(namebuf+len, name); /* XXX check for overflow */
+			strcat(namebuf, suffix); /* XXX ditto */
+			fp = fopen(namebuf, "r");
+			if (fp != NULL)
+				break;
+		}
+	}
+	return fp;
+}
+
+static object *
+load_module(ctx, name)
+	context *ctx;
+	char *name;
+{
+	object *m;
+	char **p;
+	FILE *fp;
+	node *n, *mh;
+	int err;
+	object *mtab;
+	object *save_locals, *save_globals;
+	
+	mtab = sysget("modules");
+	if (mtab == NULL || !is_dictobject(mtab)) {
+		errno = EBADF;
+		return NULL;
+	}
+	fp = open_module(name, ".py");
+	if (fp == NULL) {
+		/* XXX Compatibility hack */
+		fprintf(stderr,
+			"Can't find '%s.py' in sys.path, trying '%s'\n",
+			name, name);
+		fp = open_module(name, "");
+	}
+	if (fp == NULL) {
+		name_error(ctx, name);
+		return NULL;
+	}
+#ifdef DEBUG
+	fprintf(stderr, "Reading module %s from file '%s'\n", name, namebuf);
+#endif
+	err = parseinput(fp, file_input, &n);
+	fclose(fp);
+	if (err != E_DONE) {
+		input_error(ctx, err);
+		return NULL;
+	}
+	save_locals = ctx->ctx_locals;
+	INCREF(save_locals);
+	save_globals = ctx->ctx_globals;
+	INCREF(save_globals);
+	define_module(ctx, name);
+	exec_node(ctx, n);
+	DECREF(ctx->ctx_locals);
+	ctx->ctx_locals = save_locals;
+	DECREF(ctx->ctx_globals);
+	ctx->ctx_globals = save_globals;
+	/* XXX need to free the tree n here; except referenced defs */
+	if (ctx->ctx_exception) {
+		dictremove(mtab, name); /* Undefine the module */
+		return NULL;
+	}
+	m = dictlookup(mtab, name);
+	if (m == NULL) {
+		error(ctx, "module not defined after loading");
+		return NULL;
+	}
+	return m;
+}
+
+object *
+import_module(ctx, name)
+	context *ctx;
+	char *name;
+{
+	object *m;
+	object *mtab;
+	mtab = sysget("modules");
+	if (mtab == NULL || !is_dictobject(mtab)) {
+		error(ctx, "bad sys.modules");
+		return NULL;
+	}
+	if ((m = dictlookup(mtab, name)) == NULL) {
+		m = load_module(ctx, name);
+	}
+	return m;
+}