NetBSD/gnu/dist/postfix/global/file_id.c

78 lines
1.6 KiB
C

/*++
/* NAME
/* file_id 3
/* SUMMARY
/* file ID printable representation
/* SYNOPSIS
/* #include <file_id.h>
/*
/* const char *get_file_id(fd)
/* int fd;
/*
/* int check_file_id(fd, id)
/* int fd;
/* const char *id;
/* DESCRIPTION
/* get_file_id() queries the operating system for the unique identifier
/* for the specified file and returns a printable representation.
/* The result is volatile. Make a copy if it is to be used for any
/* appreciable amount of time.
/*
/* check_file_id() tests if an open file matches the given
/* printable FILE ID representation.
/*
/* Arguments:
/* .IP fd
/* A valid file descriptor that is associated with an open file.
/* .IP id
/* Printable file ID.
/* DIAGNOSTICS
/* All errors are fatal.
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/* Wietse Venema
/* IBM T.J. Watson Research
/* P.O. Box 704
/* Yorktown Heights, NY 10598, USA
/*--*/
/* System library. */
#include <sys_defs.h>
#include <sys/stat.h>
#include <string.h>
/* Utility library */
#include <msg.h>
#include <vstring.h>
/* Global library. */
#include "file_id.h"
/* get_file_id - lookup file ID, convert to printable form */
const char *get_file_id(int fd)
{
static VSTRING *result;
struct stat st;
if (result == 0)
result = vstring_alloc(1);
if (fstat(fd, &st) < 0)
msg_fatal("fstat: %m");
vstring_sprintf(result, "%X", (int) st.st_ino);
return (vstring_str(result));
}
/* check_file_id - make sure file name matches ID */
int check_file_id(int fd, const char *name)
{
return (strcmp(get_file_id(fd), name));
}