389-ds-base/ldap/servers/slapd/tools/mkdep.c

/** BEGIN COPYRIGHT BLOCK
 * This Program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation; version 2 of the License.
 * 
 * This Program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License along with
 * this Program; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place, Suite 330, Boston, MA 02111-1307 USA.
 * 
 * In addition, as a special exception, Red Hat, Inc. gives You the additional
 * right to link the code of this Program with code not covered under the GNU
 * General Public License ("Non-GPL Code") and to distribute linked combinations
 * including the two, subject to the limitations in this paragraph. Non-GPL Code
 * permitted under this exception must only link to the code of this Program
 * through those well defined interfaces identified in the file named EXCEPTION
 * found in the source code files (the "Approved Interfaces"). The files of
 * Non-GPL Code may instantiate templates or use macros or inline functions from
 * the Approved Interfaces without causing the resulting work to be covered by
 * the GNU General Public License. Only Red Hat, Inc. may make changes or
 * additions to the list of Approved Interfaces. You must obey the GNU General
 * Public License in all respects for all of the Program code and other code used
 * in conjunction with the Program except the Non-GPL Code covered by this
 * exception. If you modify this file, you may extend this exception to your
 * version of the file, but you are not obligated to do so. If you do not wish to
 * provide this exception without modification, you must delete this exception
 * statement from your version and license this file solely under the GPL without
 * exception. 
 * 
 * 
 * Copyright (C) 2001 Sun Microsystems, Inc. Used by permission.
 * Copyright (C) 2005 Red Hat, Inc.
 * All rights reserved.
 * END COPYRIGHT BLOCK **/

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

/*
 * Originally by Linus Torvalds.
 * Smart CONFIG_* processing by Werner Almesberger, Michael Chastain.
 * Lobotomized by Robey Pointer.
 *
 * Usage: mkdep file ...
 * 
 * Read source files and output makefile dependency lines for them.
 * I make simple dependency lines for #include "*.h".
 */

#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#ifdef WINNT
#include <windows.h>
#include <winbase.h>
#include <io.h>
#else
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#endif


char __depname[512] = "\n\t@touch ";
#define depname (__depname+9)
int hasdep;

char *outdir = ".";

struct path_struct {
	int len;
	char buffer[256-sizeof(int)];
} path = { 0, "" };


#ifdef WINNT
#define EXISTS(_fn)	_access(_fn, 00)
#else
#define EXISTS(_fn)	access(_fn, F_OK)
#endif

/*
 * Handle an #include line.
 */
void handle_include(const char * name, int len)
{
    memcpy(path.buffer+path.len, name, len);
    path.buffer[path.len+len] = '\0';
    if (EXISTS(path.buffer))
	return;

    if (!hasdep) {
	hasdep = 1;
        /* don't use outdir if it's a .h file */
        if ((strlen(depname) > 2) &&
            (strcmp(depname + strlen(depname) - 2, ".h") == 0)) {
            /* skip using the outdir */
        } else {
            if (outdir)
                printf("%s/", outdir);
        }
	printf("%s:", depname);
    }
    printf(" \\\n   %s", path.buffer);
}


/* --- removed weird functions to try to emulate asm ---
 * (turns out it's faster just to scan thru a char*)
 */

#define GETNEXT { current = *next++; if (next >= end) break; }

/*
 * State machine macros.
 */
#define CASE(c,label) if (current == c) goto label
#define NOTCASE(c,label) if (current != c) goto label

/*
 * Yet another state machine speedup.
 */
#define MAX2(a,b) ((a)>(b)?(a):(b))
#define MIN2(a,b) ((a)<(b)?(a):(b))
#define MAX4(a,b,c,d) (MAX2(a,MAX2(b,MAX2(c,d))))
#define MIN4(a,b,c,d) (MIN2(a,MIN2(b,MIN2(c,d))))



/*
 * The state machine looks for (approximately) these Perl regular expressions:
 *
 *    m|\/\*.*?\*\/|
 *    m|'.*?'|
 *    m|".*?"|
 *    m|#\s*include\s*"(.*?)"|
 *
 * About 98% of the CPU time is spent here, and most of that is in
 * the 'start' paragraph.  Because the current characters are
 * in a register, the start loop usually eats 4 or 8 characters
 * per memory read.  The MAX6 and MIN6 tests dispose of most
 * input characters with 1 or 2 comparisons.
 */
void state_machine(const char * map, const char * end)
{
	register const char * next = map;
	register const char * map_dot;
	register unsigned char current;

	for (;;) {
start:
	GETNEXT
__start:
	if (current > MAX4('/','\'','"','#')) goto start;
	if (current < MIN4('/','\'','"','#')) goto start;
	CASE('/',  slash);
	CASE('\'', squote);
	CASE('"',  dquote);
	CASE('#',  pound);
	goto start;

/* / */
slash:
	GETNEXT
	NOTCASE('*', __start);
slash_star_dot_star:
	GETNEXT
__slash_star_dot_star:
	NOTCASE('*', slash_star_dot_star);
	GETNEXT
	NOTCASE('/', __slash_star_dot_star);
	goto start;

/* '.*?' */
squote:
	GETNEXT
	CASE('\'', start);
	NOTCASE('\\', squote);
	GETNEXT
	goto squote;

/* ".*?" */
dquote:
	GETNEXT
	CASE('"', start);
	NOTCASE('\\', dquote);
	GETNEXT
	goto dquote;

/* #\s* */
pound:
	GETNEXT
	CASE(' ',  pound);
	CASE('\t', pound);
	CASE('i',  pound_i);
	goto __start;

/* #\s*i */
pound_i:
	GETNEXT NOTCASE('n', __start);
	GETNEXT NOTCASE('c', __start);
	GETNEXT NOTCASE('l', __start);
	GETNEXT NOTCASE('u', __start);
	GETNEXT NOTCASE('d', __start);
	GETNEXT NOTCASE('e', __start);
	goto pound_include;

/* #\s*include\s* */
pound_include:
	GETNEXT
	CASE(' ',  pound_include);
	CASE('\t', pound_include);
	map_dot = next;
	CASE('"',  pound_include_dquote);
	goto __start;

/* #\s*include\s*"(.*)" */
pound_include_dquote:
	GETNEXT
	CASE('\n', start);
	NOTCASE('"', pound_include_dquote);
	handle_include(map_dot, next - map_dot - 1);
	goto start;

    }
}


#ifdef WINNT

/*
 * Alternate implementation of do_depend() for NT
 * (NT has its own wacky versions of open/mmap/close)
 */
void do_depend(const char *filename, const char *command)
{
    HANDLE fd, mapfd;
    BY_HANDLE_FILE_INFORMATION st;
    char *map;

    fd = CreateFile(filename, GENERIC_READ, FILE_SHARE_READ, NULL,
	OPEN_EXISTING, FILE_FLAG_SEQUENTIAL_SCAN, NULL);
    if (fd == INVALID_HANDLE_VALUE) {
	fprintf(stderr, "NT error opening '%s'\n", filename);
	return;
    }
    if (! GetFileInformationByHandle(fd, &st)) {
	fprintf(stderr, "NT error getting stat on '%s'\n", filename);
	CloseHandle(fd);
	return;
    }
    if (st.nFileSizeLow == 0) {
	fprintf(stderr, "%s is empty\n", filename);
	CloseHandle(fd);
	return;
    }

    mapfd = CreateFileMapping(fd, NULL, PAGE_READONLY, st.nFileSizeHigh,
	st.nFileSizeLow, NULL);
    if (mapfd == NULL) {
	fprintf(stderr, "NT error creating file mapping of '%s'\n",
	    filename);
	CloseHandle(fd);
	return;
    }
    map = MapViewOfFile(mapfd, FILE_MAP_READ, 0, 0, 0);
    if (map == NULL) {
	fprintf(stderr, "NT error creating mapped view of '%s'\n",
	    filename);
	CloseHandle(mapfd);
	CloseHandle(fd);
	return;
    }

    hasdep = 0;
    state_machine(map, map+st.nFileSizeLow);
    if (hasdep)
	puts(command);

    UnmapViewOfFile(map);
    CloseHandle(mapfd);
    CloseHandle(fd);
}

#else

/*
 * Generate dependencies for one file.
 */
void do_depend(const char * filename, const char * command)
{
	int mapsize;
	int pagesizem1 = getpagesize()-1;
	int fd;
	struct stat st;
	char * map;

	fd = open(filename, O_RDONLY);
	if (fd < 0) {
		perror(filename);
		return;
	}

	fstat(fd, &st);
	if (st.st_size == 0) {
		fprintf(stderr,"%s is empty\n",filename);
		close(fd);
		return;
	}

	mapsize = st.st_size;
	mapsize = (mapsize+pagesizem1) & ~pagesizem1;
	map = mmap(NULL, mapsize, PROT_READ, MAP_PRIVATE, fd, 0);
	if ((long) map == -1) {
		perror("mkdep: mmap");
		close(fd);
		return;
	}
	if ((unsigned long) map % sizeof(unsigned long) != 0)
	{
		fprintf(stderr, "do_depend: map not aligned\n");
		exit(1);
	}

	hasdep = 0;
	state_machine(map, map+st.st_size);
	if (hasdep)
		puts(command);

	munmap(map, mapsize);
	close(fd);
}

#endif


/*
 * Generate dependencies for all files.
 */
int main(int argc, char **argv)
{
    int len;

    while (--argc > 0) {
	const char *filename = *++argv;
	const char *command  = __depname;

	if (strcmp(filename, "-o") == 0) {
	    outdir = *++argv;
	    argc--;
	    continue;
	}
	len = strlen(filename);
	memcpy(depname, filename, len+1);
	if (len > 2 && filename[len-2] == '.') {
	    if (filename[len-1] == 'c' || filename[len-1] == 'S') {
		depname[len-1] = 'o';
		command = "";
	    }
	}
	do_depend(filename, command);
    }
    return 0;
}