From: Colin P. Mccabe <colin@cmccabe.xyz>
Date: Thu, 20 Dec 2018 21:48:09 +0000 (-0800)
Subject: Some improvements to random_word
X-Git-Url: http://www.club.cc.cmu.edu/~cmccabe/cgi-bin/gitweb.cgi?p=cmccabe-bin;a=commitdiff_plain;h=0199f6555377ad9d2bc9fc40f3c3df2c081d2f57

Some improvements to random_word

* Change name from random-word to random_word.
* Make the path to the dictionary configurable.
* Add random_word to the Makefile.
---

diff --git a/.gitignore b/.gitignore
index 74827ca..da93917 100644
--- a/.gitignore
+++ b/.gitignore
@@ -15,6 +15,7 @@ hexconv
 msgpack-translate
 directory_merge
 pickrand
+random_word
 audiobooker
 
 #
diff --git a/Makefile b/Makefile
index a5aeef5..db04831 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 CFLAGS=-Wall -O2
 
-all:		audiobooker bytor errno_speak show_default_sockopts simple_time vimstart hexconv
+all:		audiobooker bytor errno_speak show_default_sockopts random_word simple_time vimstart hexconv
 
 audiobooker:
 	go build audiobooker.go
@@ -18,5 +18,7 @@ vimstart:	vimstart.o
 
 hexconv:	hexconv.o
 
+random_word:	random_word.o
+
 clean:
 	rm -rf bytor errno_speak show_default_sockopts simple_time vimstart hexconv *.o
diff --git a/random-word.c b/random_word.c
similarity index 69%
rename from random-word.c
rename to random_word.c
index d751d06..f29bc7d 100644
--- a/random-word.c
+++ b/random_word.c
@@ -3,8 +3,9 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/time.h>
+#include <unistd.h>
 
-#define DICT "/usr/share/dict/linux.words"
+#define DEFAULT_DICT_PATH "/usr/share/dict/linux.words"
 #define STARTING_SZ 8192
 #define MAX_ARRAY_SZ 1073741824
 
@@ -86,21 +87,54 @@ static const char* choose_random_word(struct dict *dict)
 	return dict->words[choice];
 }
 
-int main(void)
+static void print_usage(char *program_name)
+{
+	printf("%s: prints a random word from a linebreak-delimited file.\n",
+	       program_name);
+	printf("options:\n");
+	printf("\t-d: the dictionary file to use.  Default: %s.\n",
+	       DEFAULT_DICT_PATH);
+	printf("\t-h: this help message.\n");
+}
+
+static void parse_args(char **argv, int argc, char **dict_path)
+{
+	char c;
+	*dict_path = DEFAULT_DICT_PATH;
+	opterr = 0;
+	while ((c = getopt(argc, argv, "d:h")) != -1) {
+		switch (c) {
+		case 'd':
+			*dict_path = optarg;
+			break;
+		case 'h':
+			print_usage(argv[0]);
+			exit(0);
+			break;
+		default:
+			fprintf (stderr, "Argument parsing error.\n");
+			exit(1);
+		}
+	}
+}
+
+int main(int argc, char **argv)
 {
 	FILE *fp;
+	char *dict_path;
 	const char *word;
 	struct dict *dict;
 	struct timeval tv;
 
+	parse_args(argv, argc, &dict_path);
 	gettimeofday(&tv, NULL);
 	srandom(tv.tv_usec * tv.tv_sec);
 
-	fp = fopen(DICT, "r");
+	fp = fopen(dict_path, "r");
 	if (! fp) {
 		int err = errno;
 		fprintf(stderr, "failed to open %s: %s (%d).\n",
-			DICT, strerror(err), err);
+			dict_path, strerror(err), err);
 		return 1;
 	}
 	dict = read_dict(fp);