--- lbbs/src/article_cache.c	2025/05/29 09:44:01	1.1
+++ lbbs/src/article_cache.c	2025/05/30 12:51:00	1.2
@@ -15,18 +15,177 @@
  ***************************************************************************/
 
 #include "article_cache.h"
+#include "log.h"
+#include <errno.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <strings.h>
+#define _POSIX_C_SOURCE 200809L
+#include <string.h>
 
-int article_cache_generate(const char *cache_dir, const ARTICLE *p_article, const char *content)
+#define ARTICLE_HEADER_MAX_LEN 4096
+
+inline static int article_cache_path(char *file_path, size_t buf_len, const char *cache_dir, const ARTICLE *p_article)
+{
+	if (file_path == NULL || cache_dir == NULL || p_article == NULL)
+	{
+		log_error("article_cache_path() NULL pointer error\n");
+		return -1;
+	}
+
+	snprintf(file_path, buf_len, "%s%d", cache_dir, p_article->cid);
+
+	return 0;
+}
+
+int article_cache_generate(const char *cache_dir, const ARTICLE *p_article, const char *content, int overwrite)
 {
+	char data_file[FILE_PATH_LEN];
+	int fd;
+	ARTICLE_CACHE cache;
+	size_t buf_size;
+
+	if (cache_dir == NULL || p_article == NULL || content == NULL)
+	{
+		log_error("article_cache_generate() NULL pointer error\n");
+		return -1;
+	}
+
+	if (article_cache_path(data_file, sizeof(data_file), cache_dir, p_article) < 0)
+	{
+		log_error("article_cache_path(dir=%s, cid=%d) error\n", cache_dir, p_article->cid);
+		return -1;
+	}
+
+	if (!overwrite)
+	{
+		if ((fd = open(data_file, O_RDONLY)) != -1) // check data file
+		{
+			close(fd);
+			return 0;
+		}
+	}
+
+	buf_size = ARTICLE_HEADER_MAX_LEN + strlen(content) + 1;
+	cache.p_data = malloc(buf_size);
+	if (cache.p_data == NULL)
+	{
+		log_error("malloc(size=%ld) error OOM\n", buf_size);
+		return -1;
+	}
+
+	if ((fd = open(data_file, O_WRONLY | O_CREAT | O_TRUNC, 0640)) == -1)
+	{
+		log_error("open(%s) error (%d)\n", data_file, errno);
+		return -2;
+	}
+
+	// TODO: Generate article header
+	cache.data_len = (size_t)snprintf(cache.p_data,
+									  ARTICLE_HEADER_MAX_LEN + strlen(content) + 1,
+									  "%s",
+									  content);
+
+	bzero(cache.line_offsets, sizeof(cache.line_offsets));
+	cache.line_total = split_data_lines(cache.p_data, SCREEN_COLS, cache.line_offsets, MAX_SPLIT_FILE_LINES);
+	if (cache.line_total >= MAX_SPLIT_FILE_LINES)
+	{
+		log_error("split_data_lines(%s) truncated over limit lines\n", data_file);
+	}
+
+	if (write(fd, &cache, sizeof(cache)) == -1)
+	{
+		log_error("write(%s, cache) error (%d)\n", data_file, errno);
+		close(fd);
+		return -3;
+	}
+	if (write(fd, cache.p_data, cache.data_len) == -1)
+	{
+		log_error("write(%s, data) error (%d)\n", data_file, errno);
+		close(fd);
+		return -3;
+	}
+
+	if (close(fd) == -1)
+	{
+		log_error("close(%s) error (%d)\n", data_file, errno);
+		return -2;
+	}
+
+	free(cache.p_data);
+
 	return 0;
 }
 
 int article_cache_load(ARTICLE_CACHE *p_cache, const char *cache_dir, const ARTICLE *p_article)
 {
+	char data_file[FILE_PATH_LEN];
+	int fd;
+
+	if (p_cache == NULL || cache_dir == NULL || p_article == NULL)
+	{
+		log_error("article_cache_load() NULL pointer error\n");
+		return -1;
+	}
+
+	if (article_cache_path(data_file, sizeof(data_file), cache_dir, p_article) < 0)
+	{
+		log_error("article_cache_path(dir=%s, cid=%d) error\n", cache_dir, p_article->cid);
+		return -1;
+	}
+
+	if ((fd = open(data_file, O_RDONLY)) == -1)
+	{
+		log_error("open(%s) error (%d)\n", data_file, errno);
+		return -2;
+	}
+
+	if (read(fd, (void *)p_cache, sizeof(ARTICLE_CACHE)) == -1)
+	{
+		log_error("read(%s, cache) error (%d)\n", data_file, errno);
+		close(fd);
+		return -3;
+	}
+
+	p_cache->p_data = malloc(p_cache->data_len + 1);
+	if (p_cache->p_data == NULL)
+	{
+		log_error("malloc(size=%ld) error OOM\n", p_cache->data_len + 1);
+		close(fd);
+		return -1;
+	}
+
+	if (read(fd, p_cache->p_data, p_cache->data_len) == -1)
+	{
+		log_error("read(%s, data) error (%d)\n", data_file, errno);
+		close(fd);
+		return -3;
+	}
+	p_cache->p_data[p_cache->data_len] = '\0';
+
+	if (close(fd) == -1)
+	{
+		log_error("close(%s) error (%d)\n", data_file, errno);
+		return -2;
+	}
+
 	return 0;
 }
 
 int article_cache_unload(ARTICLE_CACHE *p_cache)
 {
+	if (p_cache == NULL || p_cache->p_data == NULL)
+	{
+		log_error("article_cache_unload() NULL pointer error\n");
+		return -1;
+	}
+
+	free(p_cache->p_data);
+	p_cache->p_data = NULL;
+
 	return 0;
 }