path: root/usr.bin/cvs/util.c

/*	$OpenBSD: util.c,v 1.1 2004/07/13 22:02:40 jfb Exp $	*/
/*
 * Copyright (c) 2004 Jean-Francois Brousseau <jfb@openbsd.org>
 * All rights reserved. 
 *
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions 
 * are met: 
 *
 * 1. Redistributions of source code must retain the above copyright 
 *    notice, this list of conditions and the following disclaimer. 
 * 2. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL  DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
 */

#include <sys/types.h>
#include <sys/stat.h>

#include <md5.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

#include "cvs.h"
#include "log.h"


/* letter -> mode type map */
static const int cvs_modetypes[26] = {
	-1, -1, -1, -1, -1, -1,  1, -1, -1, -1, -1, -1, -1,
	-1,  2, -1, -1, -1, -1, -1,  0, -1, -1, -1, -1, -1,
};

/* letter -> mode map */
static const mode_t cvs_modes[3][26] = {
	{
		0,  0,       0,       0,       0,  0,  0,    /* a - g */
		0,  0,       0,       0,       0,  0,  0,    /* h - m */
		0,  0,       0,       S_IRUSR, 0,  0,  0,    /* n - u */
		0,  S_IWUSR, S_IXUSR, 0,       0             /* v - z */
	},
	{
		0,  0,       0,       0,       0,  0,  0,    /* a - g */
		0,  0,       0,       0,       0,  0,  0,    /* h - m */
		0,  0,       0,       S_IRGRP, 0,  0,  0,    /* n - u */
		0,  S_IWGRP, S_IXGRP, 0,       0             /* v - z */
	},
	{
		0,  0,       0,       0,       0,  0,  0,    /* a - g */
		0,  0,       0,       0,       0,  0,  0,    /* h - m */
		0,  0,       0,       S_IROTH, 0,  0,  0,    /* n - u */
		0,  S_IWOTH, S_IXOTH, 0,       0             /* v - z */
	}
};


/* octal -> string */
static const char *cvs_modestr[8] = {
	"", "x", "w", "wx", "r", "rx", "rw", "rwx"
};




/*
 * cvs_readrepo()
 *
 * Read the path stored in the `Repository' CVS file for a given directory
 * <dir>, and store that path into the buffer pointed to by <dst>, whose size
 * is <len>.
 */

int
cvs_readrepo(const char *dir, char *dst, size_t len)
{
	size_t dlen;
	FILE *fp;
	char repo_path[MAXPATHLEN];

	snprintf(repo_path, sizeof(repo_path), "%s/CVS/Repository", dir);

	fp = fopen(repo_path, "r");
	if (fp == NULL) {
		cvs_log(LP_ERRNO, "failed to open `%s'", repo_path);
		return (-1);
	}

	if (fgets(dst, (int)len, fp) == NULL) {
		if (ferror(fp)) {
			cvs_log(LP_ERRNO, "failed to read from `%s'",
			    repo_path);
		}
		(void)fclose(fp);
		return (-1);
	}
	dlen = strlen(dst);
	if ((dlen > 0) && (dst[dlen - 1] == '\n'))
		dst[--dlen] = '\0';

	(void)fclose(fp);

	return (0);
}


/*
 * cvs_strtomode()
 *
 * Read the contents of the string <str> and generate a permission mode from
 * the contents of <str>, which is assumed to have the mode format of CVS.
 * The CVS protocol specification states that any modes or mode types that are
 * not recognized should be silently ignored.  This function does not return
 * an error in such cases, but will issue warnings.
 * Returns 0 on success, or -1 on failure.
 */

int
cvs_strtomode(const char *str, mode_t *mode)
{
	int type;
	mode_t m;
	char buf[32], ms[4], *sp, *ep;

	m = 0;
	strlcpy(buf, str, sizeof(buf));
	sp = buf;
	ep = sp;

	for (sp = buf; ep != NULL; sp = ep + 1) {
		ep = strchr(sp, ',');
		if (ep != NULL)
			*(ep++) = '\0';

		if (sscanf(sp, "%c=%3s", (char *)&type, ms) != 2) {
			cvs_log(LP_WARN, "failed to scan mode string `%s'", sp);
			continue;
		}

		if ((type <= 'a') || (type >= 'z') ||
		    (cvs_modetypes[type - 'a'] == -1)) {
			cvs_log(LP_WARN,
			    "invalid mode type `%c'"
			    " (`u', `g' or `o' expected), ignoring", type);
			continue;
		}

		/* make type contain the actual mode index */
		type = cvs_modetypes[type - 'a'];

		for (sp = ms; *sp != '\0'; sp++) {
			if ((*sp <= 'a') || (*sp >= 'z') ||
			    (cvs_modes[type][*sp - 'a'] == 0)) {
				cvs_log(LP_WARN,
				    "invalid permission bit `%c'", *sp);
			}
			else
				m |= cvs_modes[type][*sp - 'a'];
		}
	}

	*mode = m;

	return (0);
}


/*
 * cvs_modetostr()
 *
 * Returns 0 on success, or -1 on failure.
 */

int
cvs_modetostr(mode_t mode, char *buf, size_t len)
{
	size_t l;
	char tmp[16], *bp;
	mode_t um, gm, om;

	um = (mode & S_IRWXU) >> 6;
	gm = (mode & S_IRWXG) >> 3;
	om = mode & S_IRWXO;

	bp = buf;
	*bp = '\0';
	l = 0;

	if (um) {
		snprintf(tmp, sizeof(tmp), "u=%s", cvs_modestr[um]);
		l = strlcat(buf, tmp, len); 
	}
	if (gm) {
		if (um)
			strlcat(buf, ",", len);
		snprintf(tmp, sizeof(tmp), "g=%s", cvs_modestr[gm]);
		strlcat(buf, tmp, len); 
	}
	if (om) {
		if (um || gm)
			strlcat(buf, ",", len);
		snprintf(tmp, sizeof(tmp), "o=%s", cvs_modestr[gm]);
		strlcat(buf, tmp, len); 
	}

	return (0);
}


/*
 * cvs_cksum()
 *
 * Calculate the MD5 checksum of the file whose path is <file> and generate
 * a CVS-format 32 hex-digit string, which is stored in <dst>, whose size is
 * given in <len> and must be at least 33.
 * Returns 0 on success, or -1 on failure.
 */

int
cvs_cksum(const char *file, char *dst, size_t len)
{
	if (len < CVS_CKSUM_LEN) {
		cvs_log(LP_WARN, "buffer too small for checksum");
		return (-1);
	}
	if (MD5File(file, dst) == NULL) {
		cvs_log(LP_ERRNO, "failed to generate file checksum");
		return (-1);
	}

	return (0);
}


/*
 * cvs_splitpath()
 *
 * Split a path <path> into the directory portion and the filename portion
 * and copy them in <dir> and <file>, whose lengths are <dlen> and <flen>,
 * unless they are NULL.
 * Returns 0 on success, or -1 on failure.
 */

int
cvs_splitpath(const char *path, char *dir, size_t dlen, char *file, size_t flen)
{
	size_t rlen;
	const char *sp;
	struct stat st;

	sp = strrchr(path, '/');
	if (sp == NULL) {
		if (stat(path, &st) == -1)
			return (-1);

		if (S_ISDIR(st.st_mode)) {
			if (dir != NULL)
				strlcpy(dir, path, dlen);
			if (file != NULL)
				file[0] = '\0';
		}
		else {
			if (file != NULL)
				strlcpy(file, path, flen);
			if (dir != NULL)
				strlcpy(dir, ".", dlen);
		}
	}
	else {
		rlen = MIN(dlen - 1, sp - path);
		if (dir != NULL) {
			strncpy(dir, path, rlen);
			dir[rlen] = '\0';
		}

		sp++;
		if (file != NULL)
			strlcpy(file, sp, flen);
	}

	return (0);
}


/*
 * cvs_getargv()
 *
 * Parse a line contained in <line> and generate an argument vector by
 * splitting the line on spaces and tabs.  The resulting vector is stored in
 * <argv>, which can accept up to <argvlen> entries.
 * Returns the number of arguments in the vector, or -1 if an error occured.
 */

int
cvs_getargv(const char *line, char **argv, int argvlen)
{
	u_int i;
	int argc, err;
	char linebuf[256], qbuf[128], *lp, *cp, *arg;

	strlcpy(linebuf, line, sizeof(linebuf));
	memset(argv, 0, sizeof(argv));
	argc = 0;

	/* build the argument vector */
	err = 0;
	for (lp = linebuf; lp != NULL;) {
		if (*lp == '"') {
			/* double-quoted string */
			lp++;
			i = 0;
			memset(qbuf, 0, sizeof(qbuf));
			while (*lp != '"') {
				if (*lp == '\0') {
					cvs_log(LP_ERR, "no terminating quote");
					err++;
					break;
				}
				else if (*lp == '\\')
					lp++;

				qbuf[i++] = *lp++; 
				if (i == sizeof(qbuf)) {
					err++;
					break;
				}
			}

			arg = qbuf;
		}
		else {
			cp = strsep(&lp, " \t");
			if (cp == NULL)
				break;
			else if (*cp == '\0')
				continue;

			arg = cp;
		}

		argv[argc] = strdup(arg);
		if (argv[argc] == NULL) {
			cvs_log(LP_ERRNO, "failed to copy argument");
			err++;
			break;
		}
		argc++;
	}

	if (err) {
		/* ditch the argument vector */
		for (i = 0; i < (u_int)argc; i++)
			free(argv[i]);
		argc = -1;
	}

	return (argc);
}


/*
 * cvs_freeargv()
 *
 * Free an argument vector previously generated by cvs_getargv().
 */

void
cvs_freeargv(char **argv, int argc)
{
	int i;

	for (i = 0; i < argc; i++)
		free(argv[i]);
}