kamailio/ut.c

/*
 * various general purpose functions
 *
 * Copyright (C) 2001-2003 FhG Fokus
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, 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.
 *
 */


/** Kamailio core :: various general purpose/utility functions.
 * @file ut.c
 * @ingroup core
 * Module: core
 */

#include <sys/types.h>
#include <pwd.h>
#include <grp.h>
#include <stdlib.h>
#include <time.h>
#include <sys/utsname.h> /* uname() */
#include <libgen.h>


#include "ut.h"
#include "mem/mem.h"
#include "globals.h"

/* global buffer for ut.h int2str() */
char ut_buf_int2str[INT2STR_MAX_LEN];


/* converts a username into uid:gid,
 * returns -1 on error & 0 on success */
int user2uid(int* uid, int* gid, char* user)
{
	char* tmp;
	struct passwd *pw_entry;
	
	if (user){
		*uid=strtol(user, &tmp, 10);
		if ((tmp==0) ||(*tmp)){
			/* maybe it's a string */
			pw_entry=getpwnam(user);
			if (pw_entry==0){
				goto error;
			}
			*uid=pw_entry->pw_uid;
			if (gid) *gid=pw_entry->pw_gid;
		}
		return 0;
	}
error:
	return -1;
}



/* converts a group name into a gid
 * returns -1 on error, 0 on success */
int group2gid(int* gid, char* group)
{
	char* tmp;
	struct group  *gr_entry;
	
	if (group){
		*gid=strtol(group, &tmp, 10);
		if ((tmp==0) ||(*tmp)){
			/* maybe it's a string */
			gr_entry=getgrnam(group);
			if (gr_entry==0){
				goto error;
			}
			*gid=gr_entry->gr_gid;
		}
		return 0;
	}
 error:
	return -1;
}


/*
 * Replacement of timegm (does not exists on all platforms
 * Taken from 
 * http://lists.samba.org/archive/samba-technical/2002-November/025737.html
 */
time_t _timegm(struct tm* t)
{
	time_t tl, tb;
	struct tm* tg;

	t->tm_isdst = 0;
	tl = mktime(t);
	if (tl == -1) {
		t->tm_hour--;
		tl = mktime (t);
		if (tl == -1) {
			return -1; /* can't deal with output from strptime */
		}
		tl += 3600;
	}
	
	tg = gmtime(&tl);
	tg->tm_isdst = 0;
	tb = mktime(tg);
	if (tb == -1) {
		tg->tm_hour--;
		tb = mktime (tg);
		if (tb == -1) {
			return -1; /* can't deal with output from gmtime */
		}
		tb += 3600;
	}
	return (tl - (tb - tl));
}


/* Convert time_t value that is relative to local timezone to UTC */
time_t local2utc(time_t in)
{
	struct tm* tt;
	tt = gmtime(&in);
	tt->tm_isdst = -1;
	return mktime(tt);
}


/* Convert time_t value in UTC to to value relative to local time zone */
time_t utc2local(time_t in)
{
	struct tm* tt;
	tt = localtime(&in);
#ifdef HAVE_TIMEGM
	return timegm(tt);
#else
	return _timegm(tt);
#endif
}


/*
 * Return str as zero terminated string allocated
 * using pkg_malloc
 */
char* as_asciiz(str* s)
{
    char* r;

    r = (char*)pkg_malloc(s->len + 1);
    if (!r) {
		ERR("Out of memory\n");
		return 0;
    }
    memcpy(r, s->s, s->len);
    r[s->len] = '\0';
    return r;
}



/* return system version (major.minor.minor2) as
 *  (major<<16)|(minor)<<8|(minor2)
 * (if some of them are missing, they are set to 0)
 * if the parameters are not null they are set to the coresp. part 
 */
unsigned int get_sys_version(int* major, int* minor, int* minor2)
{
	struct utsname un;
	int m1;
	int m2;
	int m3;
	char* p;
	
	memset (&un, 0, sizeof(un));
	m1=m2=m3=0;
	/* get sys version */
	uname(&un);
	m1=strtol(un.release, &p, 10);
	if (*p=='.'){
		p++;
		m2=strtol(p, &p, 10);
		if (*p=='.'){
			p++;
			m3=strtol(p, &p, 10);
		}
	}
	if (major) *major=m1;
	if (minor) *minor=m2;
	if (minor2) *minor2=m3;
	return ((m1<<16)|(m2<<8)|(m3));
}



/** transform a relative pathname into an absolute one.
 * @param base  - base file, used to extract the absolute path prefix.
 *                Might be NULL, in which case the path of the ser.cfg is
 *                used.
 * @param file  - file path to be transformed. If it's already absolute
 *                (starts with '/') is left alone. If not the result will
 *                be `dirname base`/file.
 * @return  pkg allocated asciiz string or 0 on error.
 */
char* get_abs_pathname(str* base, str* file)
{
	str ser_cfg;
	char* buf, *dir, *res;
	int len;
  	
	if (base == NULL) {
		ser_cfg.s = cfg_file;
		ser_cfg.len = strlen(cfg_file);
		base = &ser_cfg;
	}
	
	if (!base->s || base->len <= 0 || base->s[0] != '/') {
		BUG("get_abs_pathname: Base file must be absolute pathname: "
			"'%.*s'\n", STR_FMT(base));
		return NULL;
	}
	
	if (!file || !file->s || file->len <= 0) {
		BUG("get_abs_pathname: Invalid 'file' parameter\n");
		return NULL;
	}
	
	if (file->s[0] == '/') {
		/* This is an absolute pathname, make a zero terminated
		 * copy and use it as it is */
		if ((res = pkg_malloc(file->len+1)) == NULL) {
			ERR("get_abs_pathname: No memory left (pkg_malloc failed)\n");
			return NULL;
		}
		memcpy(res, file->s, file->len);
		res[file->len]=0;
	} else {
		/* This is not an absolute pathname, make it relative
		 * to the location of the base file
		 */
		/* Make a copy, function dirname may modify the string */
		if ((buf = pkg_malloc(base->len+1)) == NULL) {
			ERR("get_abs_pathname: No memory left (pkg_malloc failed)\n");
			return NULL;
		}
		memcpy(buf, base->s, base->len);
		buf[base->len]=0;
		dir = dirname(buf);
		
		len = strlen(dir);
		if ((res = pkg_malloc(len + 1 + file->len + 1)) == NULL) {
			ERR("get_abs_pathname: No memory left (pkg_malloc failed)\n");
			pkg_free(buf);
			return NULL;
		}
		memcpy(res, dir, len);
		res[len] = '/';
		memcpy(res + len + 1, file->s, file->len);
		res[len + 1 + file->len] = '\0';
		pkg_free(buf);
	}
	return res;
}


/**
 * @brief search for occurence of needle in text
 * @return pointer to start of needle in text or NULL if the needle
 *	is not found
 */
char *str_search(str *text, str *needle)
{
    char *p;

    if(text==NULL || text->s==NULL || needle==NULL || needle->s==NULL
			|| text->len<needle->len)
        return NULL;

    for (p = text->s; p <= text->s + text->len - needle->len; p++) {
        if (*p == *needle->s && memcmp(p, needle->s, needle->len)==0) {
            return p;
        }
    }

    return NULL;
}

/*
 * ser_memmem() returns the location of the first occurrence of data
 * pattern b2 of size len2 in memory block b1 of size len1 or
 * NULL if none is found. Obtained from NetBSD.
 */
void * ser_memmem(const void *b1, const void *b2, size_t len1, size_t len2)
{
	/* Initialize search pointer */
	char *sp = (char *) b1;

	/* Initialize pattern pointer */
	char *pp = (char *) b2;

	/* Initialize end of search address space pointer */
	char *eos = sp + len1 - len2;

	/* Sanity check */
	if(!(b1 && b2 && len1 && len2))
		return NULL;

	while (sp <= eos) {
		if (*sp == *pp)
			if (memcmp(sp, pp, len2) == 0)
				return sp;

			sp++;
	}

	return NULL;
}

/*
 * ser_memrmem() returns the location of the last occurrence of data
 * pattern b2 of size len2 in memory block b1 of size len1 or
 * NULL if none is found.
 */
void * ser_memrmem(const void *b1, const void *b2, size_t len1, size_t len2)
{
	/* Initialize search pointer */
	char *sp = (char *) b1 + len1 - len2;

	/* Initialize pattern pointer */
	char *pp = (char *) b2;

	/* Initialize end of search address space pointer */
	char *eos = (char *) b1;

	/* Sanity check */
	if(!(b1 && b2 && len1 && len2))
		return NULL;

	while (sp >= eos) {
		if (*sp == *pp)
			if (memcmp(sp, pp, len2) == 0)
				return sp;

			sp--;
	}

	return NULL;
}