Add my PD implementation of the SCCS help command, which prints help from

files in the format used by SCCS, given a key.  It behaves exactly like the
``proper'' SCCS help command, from what testing I can do.

2 files changed, 146 insertions, 0 deletions

diff --git a/usr.bin/help/Makefile b/usr.bin/help/Makefile
new file mode 100644
index 0000000..67b34e9
--- /dev/null
+++ b/usr.bin/help/Makefile
@@ -0,0 +1,6 @@
+# $FreeBSD$
+
+PROG=	help
+NOMAN=	noman
+
+.include <bsd.prog.mk>
diff --git a/usr.bin/help/help.c b/usr.bin/help/help.c
new file mode 100644
index 0000000..beeb1e9
--- /dev/null
+++ b/usr.bin/help/help.c
@@ -0,0 +1,140 @@
+/*
+ * 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 <sys/stat.h>
+#include <ctype.h>
+#include <err.h>
+#include <errno.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"
+
+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';
+	snprintf(path, sizeof(path), _PATH_LIBHELP "/%s", keybase);
+	free(keybase);
+	numlen = strlen(keynumber);
+
+	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 + 1) {
+				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 (found) {
+		return 0;
+	}
+fail:
+	printf("Key '%s' not found.\n", key);
+	return 1;
+}