From 403b1001a00217af1b3d673028dddd3f1747da2e Mon Sep 17 00:00:00 2001
From: Colin Patrick McCabe <cmccabe@alumni.cmu.edu>
Date: Sat, 13 Mar 2010 07:53:13 -0800
Subject: [PATCH] Add find-random-word script

---
 random-word.c |  112 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 112 insertions(+), 0 deletions(-)
 create mode 100644 random-word.c

diff --git a/random-word.c b/random-word.c
new file mode 100644
index 0000000..c75047b
--- /dev/null
+++ b/random-word.c
@@ -0,0 +1,112 @@
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#define DICT "/usr/share/dict/linux.words"
+#define STARTING_SZ 8192
+#define MAX_ARRAY_SZ 1073741824
+
+struct dict {
+	int num_words;
+	int array_sz;
+	char *words[0];
+};
+
+static int alloc_dict(struct dict **d, int array_sz)
+{
+	struct dict *nd;
+	int num_bytes;
+	if (array_sz > MAX_ARRAY_SZ) {
+		fprintf(stderr, "can't allocate a words array bigger "
+			"than %d\n", MAX_ARRAY_SZ);
+		return EINVAL;
+	}
+
+	num_bytes = sizeof(struct dict) + (array_sz * sizeof(char*));
+	nd = realloc(*d, num_bytes);
+	if (!nd) {
+		fprintf(stderr, "failed to realloc to size %d\n",
+			num_bytes);
+		return ENOSPC;
+	}
+	*d = nd;
+
+	nd->array_sz = array_sz;
+	return 0;
+}
+
+static struct dict* read_dict(FILE *fp)
+{
+	char word[500];
+	struct dict *d =
+		malloc(sizeof(struct dict) + (STARTING_SZ * sizeof(char*)));
+	if (! d) {
+		fprintf(stderr, "failed to allocate dict\n");
+		return NULL;
+	}
+	d->num_words = 0;
+	d->array_sz = STARTING_SZ;
+
+	while (1) {
+		if (! fgets(word, sizeof(word), fp)) {
+			if (ferror(fp)) {
+				int err = errno;
+				fprintf(stderr, "%s: error reading line %d: "
+					"%s (%d)\n",
+					__func__, d->num_words + 1,
+					strerror(err), err);
+			}
+			else {
+				return d;
+			}
+		}
+		d->words[d->num_words] = strdup(word);
+		if (!d->words[d->num_words]) {
+			fprintf(stderr, "failed to allocate word %d\n",
+				d->num_words);
+			free(d);
+			return NULL;
+		}
+		d->num_words++;
+		if (d->num_words >= d->array_sz) {
+			if (alloc_dict(&d, d->array_sz * 2)) {
+				free(d);
+				return NULL;
+			}
+		}
+	}
+}
+
+static const char* choose_random_word(struct dict *dict)
+{
+	int choice = random() % dict->num_words;
+
+	return dict->words[choice];
+}
+
+int main(void)
+{
+	FILE *fp;
+	const char *word;
+	struct dict *dict;
+	srandom(time(NULL));
+
+	fp = fopen(DICT, "r");
+	if (! fp) {
+		int err = errno;
+		fprintf(stderr, "failed to open %s: %s (%d).\n",
+			DICT, strerror(err), err);
+		return 1;
+	}
+	dict = read_dict(fp);
+	if (! dict)
+		return 1;
+	fclose(fp);
+
+	word = choose_random_word(dict);
+	printf("%s\n", word); 
+
+	return 0;
+}
-- 
1.6.6.rc1.39.g9a42