From 1775fc5444d59ca8a8b68e92b26aa6d6e6e42300 Mon Sep 17 00:00:00 2001
From: Nathan Fisher <nfisher.sr@gmail.com>
Date: Fri, 11 Aug 2023 23:35:23 -0400
Subject: [PATCH] Begin implementing hashmap

---
 Makefile                           |   1 +
 hmap.c                             | 105 +++++++++++++++++++++++++++++
 {test => include}/haggis_private.h |   3 +
 3 files changed, 109 insertions(+)
 create mode 100644 hmap.c
 rename {test => include}/haggis_private.h (97%)

diff --git a/Makefile b/Makefile
index 5d2a42f..b494341 100644
--- a/Makefile
+++ b/Makefile
@@ -45,6 +45,7 @@ hdrs       += include/jobq.h
 hdrs       += include/linklist.h
 
 srcs       += bytes.c
+srcs       += hmap.c
 srcs       += haggis.c
 srcs       += jobq.c
 srcs       += linklist.c
diff --git a/hmap.c b/hmap.c
new file mode 100644
index 0000000..4a7a714
--- /dev/null
+++ b/hmap.c
@@ -0,0 +1,105 @@
+/*                 _,.---._    .-._        .--.-. ,--.--------.
+ *   _,..---._   ,-.' , -  `. /==/ \  .-._/==/  //==/,  -   , -\
+ * /==/,   -  \ /==/_,  ,  - \|==|, \/ /, |==\ -\\==\.-.  - ,-./
+ * |==|   _   _\==|   .=.     |==|-  \|  | \==\- \`--`\==\- \
+ * |==|  .=.   |==|_ : ;=:  - |==| ,  | -|  `--`-'     \==\_ \
+ * |==|,|   | -|==| , '='     |==| -   _ |             |==|- |
+ * |==|  '='   /\==\ -    ,_ /|==|  /\ , |             |==|, |
+ * |==|-,   _`/  '.='. -   .' /==/, | |- |             /==/ -/
+ * `-.`.____.'     `--`--''   `--`./  `--`             `--`--`
+ *                    _ __    ,---.      .-._         .=-.-.  _,.----.
+ *                 .-`.' ,`..--.'  \    /==/ \  .-._ /==/_ /.' .' -   \
+ *                /==/, -   \==\-/\ \   |==|, \/ /, /==|, |/==/  ,  ,-'
+ *               |==| _ .=. /==/-|_\ |  |==|-  \|  ||==|  ||==|-   |  .
+ *               |==| , '=',\==\,   - \ |==| ,  | -||==|- ||==|_   `-' \
+ *               |==|-  '..'/==/ -   ,| |==| -   _ ||==| ,||==|   _  , |
+ *               |==|,  |  /==/-  /\ - \|==|  /\ , ||==|- |\==\.       /
+ *               /==/ - |  \==\ _.\=\.-'/==/, | |- |/==/. / `-.`.___.-'
+ *               `--`---'   `--`        `--`./  `--``--`-`
+ *
+ *	@(#)Copyright (c) 2023, Nathan D. Fisher.
+ *
+ *      This is free software.  It comes with NO WARRANTY.
+ *      Permission to use, modify and distribute this source code
+ *      is granted subject to the following conditions.
+ *      1/ that the above copyright notice and this notice
+ *      are preserved in all copies and that due credit be given
+ *      to the author.
+ *      2/ that any changes to this code are clearly commented
+ *      as such so that the author does not get blamed for bugs
+ *      other than his own.
+ */
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include "haggis.h"
+#include "haggis_private.h"
+
+#define FNV64_OFFSET_BASIS 14695981039346656037u
+#define FNV64_PRIME 1099511628211u
+
+uint64_t hash_fnv1a_64(uint8_t *key, size_t len) {
+    int i;
+    uint64_t hash = FNV64_OFFSET_BASIS;
+
+    for (i = 0; i < len; i++) {
+        hash = hash ^ *key;
+        hash = hash * FNV64_PRIME;
+        key++;
+    }
+    return hash;
+}
+
+struct _map_node {
+    struct _map_node *lt;
+    struct _map_node *gt;
+    uint64_t key;
+    void *data;
+};
+
+typedef struct _map_node hmap_node;
+
+typedef struct {
+    size_t capacity;
+    size_t len;
+    hmap_node *buckets;
+} hmap;
+
+hmap_node* hmap_node_init(void *key, size_t keysize, void *data) {
+    hmap_node *node;
+    uint64_t hash;
+
+    hash = hash_fnv1a_64(key, keysize);
+    node = calloc(1, sizeof(hmap_node));
+    if (node == NULL) return NULL;
+    node->key = hash;
+    node->data = data;
+    return node;
+}
+
+hmap* hmap_init() {
+    hmap* map;
+
+    map = calloc(1, sizeof(hmap));
+    if (map == NULL) return NULL;
+    map->len = 0;
+    map->capacity = 64;
+    map->buckets = calloc(64, sizeof(size_t));
+    if (map->buckets == NULL) {
+        free(map);
+        return NULL;
+    }
+    return map;
+}
+
+hmap_node* hmap_insert(hmap * map, void *key, size_t keysize, void *data) {
+    hmap_node *node;
+
+    node = hmap_node_init(key, keysize, data);
+    if (node == NULL) return NULL;
+    // todo
+}
diff --git a/test/haggis_private.h b/include/haggis_private.h
similarity index 97%
rename from test/haggis_private.h
rename to include/haggis_private.h
index 03aff19..0d10897 100644
--- a/test/haggis_private.h
+++ b/include/haggis_private.h
@@ -33,6 +33,8 @@
 #ifndef HAGGIS_PRIVATE_H
 #define HAGGIS_PRIVATE_H 1
 
+#include <stddef.h>
+#include <stdint.h>
 #include <stdio.h>
 
 #include <sys/types.h>
@@ -59,5 +61,6 @@ int haggis_load_filename(FILE *stream, haggis_filename *n);
 int haggis_store_filename(FILE *stream, haggis_filename *n);
 int haggis_load_filetype(FILE *stream, haggis_typeflag tag, haggis_filetype *file);
 int haggis_store_filetype(FILE *stream, haggis_filetype *filetype);
+uint64_t hash_fnv1a_64(uint8_t *key, size_t len);
 
 #endif // !HAGGIS_PRIVATE_H