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/*
* Author: J. Mallett <jmallett@FreeBSD.org>
* Date: May 22, 2002
* Program: help
* Description:
* Displays help from files in the format used by SCCS.
*
* This file is in the public domain.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <ctype.h>
#include <err.h>
#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
/*
* Base path to the help files.
*/
#define _PATH_LIBHELP "/usr/lib/help"
/*
* The file we check if all else fails.
*/
#define _PATH_DEFAULT _PATH_LIBHELP "/default"
/*
* The file we check for command help.
*/
#define _PATH_COMMANDS _PATH_LIBHELP "/cmds"
int help(const char *);
int
main(int argc, char *argv[])
{
char *key;
int i, rv;
rv = 0;
if (argc == 1) {
size_t len;
(void)printf("Enter the message number or SCCS command name: ");
if ((key = fgetln(stdin, &len)) == NULL) {
err(1, NULL);
}
key[len - 1] = '\0';
return help(key);
}
argc--;
argv++;
for (i = 0; i < argc; i++) {
/*
* If no error occurred this time, rv becomes 1.
*/
if (help(argv[i]) == 0) {
rv = 1;
}
}
/*
* Return 0 if at least one help() worked. Return 1 else.
*/
return rv ? 0 : 1;
}
/*
* Function: help
* Returns: 0 if no error occurrs, 1 otherwise.
* Arguments: key -- The key we are looking up help for.
* Description:
* Looks up the help for a given key.
*/
int
help(const char *key)
{
FILE *helpfile;
char path[PATH_MAX];
char *keybase, *p;
const char *keyname, *keynumber;
int helping, found;
size_t len, numlen;
found = helping = 0;
keyname = key;
keybase = strdup(keyname);
if (keybase == NULL) {
err(1, NULL);
}
p = keybase;
while (!isnumber(*p) && *p != '\0') {
++key;
++p;
}
keynumber = key;
key = keyname;
*p = '\0';
numlen = strlen(keynumber);
/*
* Try the default help file if we have a numeric key.
* If we have no numeric part of the key, use the command help.
* Or else, use the non-numeric part of the key.
*/
if (strlen(keybase) == 0) {
strlcpy(path, _PATH_DEFAULT, sizeof(path));
} else if (numlen == 0) {
keynumber = keybase;
numlen = strlen(keynumber);
strlcpy(path, _PATH_COMMANDS, sizeof(path));
} else {
snprintf(path, sizeof(path), _PATH_LIBHELP "/%s", keybase);
}
helpfile = fopen(path, "r");
if (helpfile == NULL) {
goto fail;
}
while (!feof(helpfile) && (p = fgetln(helpfile, &len)) != NULL) {
switch (*p) {
case '*':
continue;
case '-':
if (len < numlen) {
continue;
}
if (strncmp(++p, keynumber, numlen) == 0) {
found = 1;
helping = 1;
printf("\n%s:\n", key);
} else {
helping = 0;
}
continue;
default:
if (helping) {
p[len - 1] = '\0';
printf("%s\n", p);
}
continue;
}
}
fclose(helpfile);
if (keybase != NULL) {
free(keybase);
}
if (found) {
return 0;
}
fail:
if (keybase != NULL) {
free(keybase);
}
printf("Key '%s' not found.\n", key);
return 1;
}
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