view Python/pythonmain.c @ 16539:a47d93ef103a legacy-trunk

Relax the rules for using 'from ... import *' and exec in the presence of nested functions. Either is allowed in a function if it contains no defs or lambdas or the defs and lambdas it contains have no free variables. If a function is itself nested and has free variables, either is illegal. Revise the symtable to use a PySymtableEntryObject, which holds all the revelent information for a scope, rather than using a bunch of st_cur_XXX pointers in the symtable struct. The changes simplify the internal management of the current symtable scope and of the stack. Added new C source file: Python/symtable.c. (Does the Windows build process need to be updated?) As part of these changes, the initial _symtable module interface introduced in 2.1a2 is replaced. A dictionary of PySymtableEntryObjects are returned.
author Jeremy Hylton <jeremy@alum.mit.edu>
date Fri, 09 Feb 2001 22:22:18 +0000
parents 85140b354890
children
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/***********************************************************
Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
The Netherlands.

                        All Rights Reserved

Permission to use, copy, modify, and distribute this software and its 
documentation for any purpose and without fee is hereby granted, 
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in 
supporting documentation, and that the names of Stichting Mathematisch
Centrum or CWI not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior permission.

STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

******************************************************************/

/* Python interpreter main program */

#include "allobjects.h"

extern int debugging; /* Needed in parser.c, declared in pythonrun.c */
extern int verbose; /* Needed in import.c, declared in pythonrun.c */
extern int suppress_print; /* Needed in ceval.c, declared in pythonrun.c */

/* Interface to getopt(): */
extern int optind;
extern char *optarg;
extern int getopt(); /* PROTO((int, char **, char *)); -- not standardized */

extern char *getenv();

extern char *getversion();
extern char *getcopyright();

int
realmain(argc, argv)
	int argc;
	char **argv;
{
	int c;
	int sts;
	char *command = NULL;
	char *filename = NULL;
	FILE *fp = stdin;
	char *p;
	int inspect = 0;
	int unbuffered = 0;

	if ((p = getenv("PYTHONDEBUG")) && *p != '\0')
		debugging = 1;
	if ((p = getenv("PYTHONSUPPRESS")) && *p != '\0')
		suppress_print = 1;
	if ((p = getenv("PYTHONVERBOSE")) && *p != '\0')
		verbose = 1;
	if ((p = getenv("PYTHONINSPECT")) && *p != '\0')
		inspect = 1;
	if ((p = getenv("PYTHONUNBUFFERED")) && *p != '\0')
		unbuffered = 1;

#ifdef macintosh
	PyMac_InteractiveOptions(&inspect, &verbose, &suppress_print, &unbuffered, &debugging);
#endif

	while ((c = getopt(argc, argv, "c:disuv")) != EOF) {
		if (c == 'c') {
			/* -c is the last option; following arguments
			   that look like options are left for the
			   the command to interpret. */
			command = malloc(strlen(optarg) + 2);
			if (command == NULL)
				fatal("not enough memory to copy -c argument");
			strcpy(command, optarg);
			strcat(command, "\n");
			break;
		}
		
		switch (c) {

		case 'd':
			debugging++;
			break;

		case 'i':
			inspect++;
			break;

		case 's':
			suppress_print++;
			break;

		case 'u':
			unbuffered++;
			break;

		case 'v':
			verbose++;
			break;

		/* This space reserved for other options */

		default:
			fprintf(stderr,
"usage: %s [-d] [-i] [-s] [-u ] [-v] [-c cmd | file | -] [arg] ...\n",
				argv[0]);
#if !(defined(__CFM68K__) && defined(__MWERKS__))
			/* Mwerks cfm68k linker doesn't like these... */
			fprintf(stderr, "\
\n\
Options and arguments (and corresponding environment variables):\n\
-d     : debug output from parser (also PYTHONDEBUG=x)\n\
-i     : inspect interactively after running script (also PYTHONINSPECT=x)\n\
-s     : suppress the printing of top level expressions (also PYTHONSUPPRESS=x)\n\
-u     : unbuffered stdout and stderr (also PYTHONUNBUFFERED=x)\n\
-v     : verbose (trace import statements) (also PYTHONVERBOSE=x)\n\
-c cmd : program passed in as string (terminates option list)\n\
");
			/* ANSI does not allow strings > 512 chars
			   and MPW doesn't like it either -- so split it! */
			fprintf(stderr, "\
file   : program read from script file\n\
-      : program read from stdin (default; interactive mode if a tty)\n\
arg ...: arguments passed to program in sys.argv[1:]\n\
\n\
Other environment variables:\n\
PYTHONSTARTUP: file executed on interactive startup (no default)\n\
PYTHONPATH   : colon-separated list of directories prefixed to the\n\
               default module search path.  The result is sys.path.\n\
");
#endif /* !cfm68k || !mwerks */
			exit(2);
			/*NOTREACHED*/

		}
	}

	if (unbuffered) {
#ifndef MPW
		setbuf(stdout, (char *)NULL);
		setbuf(stderr, (char *)NULL);
#else
		/* On MPW (3.2) unbuffered seems to hang */
		setvbuf(stdout, (char *)NULL, _IOLBF, BUFSIZ);
		setvbuf(stderr, (char *)NULL, _IOLBF, BUFSIZ);
#endif
	}

	if (command == NULL && optind < argc && strcmp(argv[optind], "-") != 0)
		filename = argv[optind];

	if (verbose ||
	    command == NULL && filename == NULL && isatty((int)fileno(fp)))
		fprintf(stderr, "Python %s\n%s\n",
			getversion(), getcopyright());
	
	if (filename != NULL) {
		if ((fp = fopen(filename, "r")) == NULL) {
			fprintf(stderr, "%s: can't open file '%s'\n",
				argv[0], filename);
			exit(2);
		}
	}
	
	initall();
	
	if (command != NULL) {
		/* Backup optind and force sys.argv[0] = '-c' */
		optind--;
		argv[optind] = "-c";
	}

	setpythonargv(argc-optind, argv+optind);

	if (command) {
		sts = run_command(command) != 0;
	}
	else {
		if (filename == NULL && isatty((int)fileno(fp))) {
			char *startup = getenv("PYTHONSTARTUP");
#ifdef macintosh
			if (startup == NULL)
				startup = "PythonStartup";
#endif
			if (startup != NULL && startup[0] != '\0') {
				FILE *fp = fopen(startup, "r");
				if (fp != NULL) {
					(void) run_script(fp, startup);
					err_clear();
					fclose(fp);
				}
			}
		}
		sts = run(fp, filename == NULL ? "<stdin>" : filename) != 0;
		if (filename != NULL)
			fclose(fp);
	}

	if (inspect && isatty((int)fileno(stdin)) &&
	    (filename != NULL || command != NULL))
		sts = run(stdin, "<stdin>") != 0;

	goaway(sts);
	/*NOTREACHED*/
}