global.cc

这个软件的功能同我上次传的那个avifile.也是linux上的一个用于多媒体应用的源码。

#include	<config.h>
#include	<stdio.h>
#include	<unistd.h>
#ifdef		HAVE_STDLIB_H
#include	<stdlib.h>
#endif		/* HAVE_STDLIB_H */
#include	<errno.h>
#include	<ctype.h>
#include	<fcntl.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>

/* Custom headerfiles */
#include <pwd.h>

/* External variables/functions */

/* Function prototypes */

/* Global variables */

 
/* get homedir of user 'username' (username == NULL => user running this prog)
 * it returns a malloc'd string which you should free(), or NULL if user
 * does not exist
 */
char *
get_homedir(const char *username)
{
	uid_t userid = 0;
	int match_uid = 0;
	struct passwd *pwdentry;
	short foundluser = 0;
	char *homedir = NULL;

	if (!username) // this user's homedir
	{
		userid = getuid();
		match_uid = 1;
	}

	setpwent(); //rewind passwd file

	while (!foundluser && (pwdentry = getpwent()))
	{
		if (match_uid)
		{
			if (userid == pwdentry->pw_uid)
			{
				foundluser = 1;
				homedir = strdup(pwdentry->pw_dir);
			}
		}
		else 
		{
			if (!strcmp(username, pwdentry->pw_name))
			{
				foundluser = 1;
				homedir = strdup(pwdentry->pw_dir);
			}
		}
	}
	endpwent();

	if (!foundluser)
		return NULL;
	
	else return homedir;
}

/* returns a malloc()'d string */
char *
crop_whitespace(const char *string)
{
	char *orgstring, *tmpstring, *newstring;
	int index = 0;

	if (!string)
		return NULL;

	tmpstring = strdup(string);
	orgstring = tmpstring;

	while (tmpstring[0] != '\0' && isspace((int)tmpstring[0]))
		tmpstring++;

	while ( (index = strlen(tmpstring)-1) > -1 &&
		isspace((int)tmpstring[index]))
		tmpstring[index]='\0';
	
	newstring = (char*)malloc((strlen(tmpstring)+1)*sizeof(char));	
	strcpy(newstring, tmpstring);
	free(orgstring);
	return newstring;
}