/* cache.c: cache management
 *
 * Copyright (C) 2006 Lars Hjemli
 *
 * Licensed under GNU General Public License v2
 *   (see COPYING for full license text)
 *
 *
 * The cache is just a directory structure where each file is a cache slot,
 * and each filename is based on the hash of some key (e.g. the cgit url).
 * Each file contains the full key followed by the cached content for that
 * key.
 *
 */

#include "cgit.h"
#include "cache.h"

#define CACHE_BUFSIZE (1024 * 4)

struct cache_slot {
	const char *key;
	int keylen;
	int ttl;
	cache_fill_fn fn;
	void *cbdata;
	int cache_fd;
	int lock_fd;
	const char *cache_name;
	const char *lock_name;
	int match;
	struct stat cache_st;
	struct stat lock_st;
	int bufsize;
	char buf[CACHE_BUFSIZE];
};

/* Open an existing cache slot and fill the cache buffer with
 * (part of) the content of the cache file. Return 0 on success
 * and errno otherwise.
 */
static int open_slot(struct cache_slot *slot)
{
	char *bufz;
	int bufkeylen = -1;

	slot->cache_fd = open(slot->cache_name, O_RDONLY);
	if (slot->cache_fd == -1)
		return errno;

	if (fstat(slot->cache_fd, &slot->cache_st))
		return errno;

	slot->bufsize = xread(slot->cache_fd, slot->buf, sizeof(slot->buf));
	if (slot->bufsize < 0)
		return errno;

	bufz = memchr(slot->buf, 0, slot->bufsize);
	if (bufz)
		bufkeylen = bufz - slot->buf;

	slot->match = bufkeylen == slot->keylen &&
	    !memcmp(slot->key, slot->buf, bufkeylen + 1);

	return 0;
}

/* Close the active cache slot */
static int close_slot(struct cache_slot *slot)
{
	int err = 0;
	if (slot->cache_fd > 0) {
		if (close(slot->cache_fd))
			err = errno;
		else
			slot->cache_fd = -1;
	}
	return err;
}

/* Print the content of the active cache slot (but skip the key). */
static int print_slot(struct cache_slot *slot)
{
	ssize_t i, j;

	i = lseek(slot->cache_fd, slot->keylen + 1, SEEK_SET);
	if (i != slot->keylen + 1)
		return errno;

	do {
		i = j = xread(slot->cache_fd, slot->buf, sizeof(slot->buf));
		if (i > 0)
			j = xwrite(STDOUT_FILENO, slot->buf, i);
	} while (i > 0 && j == i);

	if (i < 0 || j != i)
		return errno;
	else
		return 0;
}

/* Check if the slot has expired */
static int is_expired(struct cache_slot *slot)
{
	if (slot->ttl < 0)
		return 0;
	else
		return slot->cache_st.st_mtime + slot->ttl*60 < time(NULL);
}

/* Check if the slot has been modified since we opened it.
 * NB: If stat() fails, we pretend the file is modified.
 */
static int is_modified(struct cache_slot *slot)
{
	struct stat st;

	if (stat(slot->cache_name, &st))
		return 1;
	return (st.st_ino != slot->cache_st.st_ino ||
		st.st_mtime != slot->cache_st.st_mtime ||
		st.st_size != slot->cache_st.st_size);
}

/* Close an open lockfile */
static int close_lock(struct cache_slot *slot)
{
	int err = 0;
	if (slot->lock_fd > 0) {
		if (close(slot->lock_fd))
			err = errno;
		else
			slot->lock_fd = -1;
	}
	return err;
}

/* Create a lockfile used to store <style>pre { line-height: 125%; }
td.linenos .normal { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
span.linenos { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
td.linenos .special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
span.linenos.special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
.highlight .hll { background-color: #ffffcc }
.highlight .c { color: #888888 } /* Comment */
.highlight .err { color: #a61717; background-color: #e3d2d2 } /* Error */
.highlight .k { color: #008800; font-weight: bold } /* Keyword */
.highlight .ch { color: #888888 } /* Comment.Hashbang */
.highlight .cm { color: #888888 } /* Comment.Multiline */
.highlight .cp { color: #cc0000; font-weight: bold } /* Comment.Preproc */
.highlight .cpf { color: #888888 } /* Comment.PreprocFile */
.highlight .c1 { color: #888888 } /* Comment.Single */
.highlight .cs { color: #cc0000; font-weight: bold; background-color: #fff0f0 } /* Comment.Special */
.highlight .gd { color: #000000; background-color: #ffdddd } /* Generic.Deleted */
.highlight .ge { font-style: italic } /* Generic.Emph */
.highlight .gr { color: #aa0000 } /* Generic.Error */
.highlight .gh { color: #333333 } /* Generic.Heading */
.highlight .gi { color: #000000; background-color: #ddffdd } /* Generic.Inserted */
.highlight .go { color: #888888 } /* Generic.Output */
.highlight .gp { color: #555555 } /* Generic.Prompt */
.highlight .gs { font-weight: bold } /* Generic.Strong */
.highlight .gu { color: #666666 } /* Generic.Subheading */
.highlight .gt { color: #aa0000 } /* Generic.Traceback */
.highlight .kc { color: #008800; font-weight: bold } /* Keyword.Constant */
.highlight .kd { color: #008800; font-weight: bold } /* Keyword.Declaration */
.highlight .kn { color: #008800; font-weight: bold } /* Keyword.Namespace */
.highlight .kp { color: #008800 } /* Keyword.Pseudo */
.highlight .kr { color: #008800; font-weight: bold } /* Keyword.Reserved */
.highlight .kt { color: #888888; font-weight: bold } /* Keyword.Type */
.highlight .m { color: #0000DD; font-weight: bold } /* Literal.Number */
.highlight .s { color: #dd2200; background-color: #fff0f0 } /* Literal.String */
.highlight .na { color: #336699 } /* Name.Attribute */
.highlight .nb { color: #003388 } /* Name.Builtin */
.highlight .nc { color: #bb0066; font-weight: bold } /* Name.Class */
.highlight .no { color: #003366; font-weight: bold } /* Name.Constant */
.highlight .nd { color: #555555 } /* Name.Decorator */
.highlight .ne { color: #bb0066; font-weight: bold } /* Name.Exception */
.highlight .nf { color: #0066bb; font-weight: bold } /* Name.Function */
.highlight .nl { color: #336699; font-style: italic } /* Name.Label */
.highlight .nn { color: #bb0066; font-weight: bold } /* Name.Namespace */
.highlight .py { color: #336699; font-weight: bold } /* Name.Property */
.highlight .nt { color: #bb0066; font-weight: bold } /* Name.Tag */
.highlight .nv { color: #336699 } /* Name.Variable */
.highlight .ow { color: #008800 } /* Operator.Word */
.highlight .w { color: #bbbbbb } /* Text.Whitespace */
.highlight .mb { color: #0000DD; font-weight: bold } /* Literal.Number.Bin */
.highlight .mf { color: #0000DD; font-weight: bold } /* Literal.Number.Float */
.highlight .mh { color: #0000DD; font-weight: bold } /* Literal.Number.Hex */
.highlight .mi { color: #0000DD; font-weight: bold } /* Literal.Number.Integer */
.highlight .mo { color: #0000DD; font-weight: bold } /* Literal.Number.Oct */
.highlight .sa { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Affix */
.highlight .sb { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Backtick */
.highlight .sc { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Char */
.highlight .dl { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Delimiter */
.highlight .sd { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Doc */
.highlight .s2 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Double */
.highlight .se { color: #0044dd; background-color: #fff0f0 } /* Literal.String.Escape */
.highlight .sh { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Heredoc */
.highlight .si { color: #3333bb; background-color: #fff0f0 } /* Literal.String.Interpol */
.highlight .sx { color: #22bb22; background-color: #f0fff0 } /* Literal.String.Other */
.highlight .sr { color: #008800; background-color: #fff0ff } /* Literal.String.Regex */
.highlight .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */
.highlight .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */
.highlight .bp { color: #003388 } /* Name.Builtin.Pseudo */
.highlight .fm { color: #0066bb; font-weight: bold } /* Name.Function.Magic */
.highlight .vc { color: #336699 } /* Name.Variable.Class */
.highlight .vg { color: #dd7700 } /* Name.Variable.Global */
.highlight .vi { color: #3333bb } /* Name.Variable.Instance */
.highlight .vm { color: #336699 } /* Name.Variable.Magic */
.highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */</style><div class="highlight"><pre><span></span><span class="cp">#ifndef UI_TAG_H</span>
<span class="cp">#define UI_TAG_H</span>

<span class="k">extern</span><span class="w"> </span><span class="kt">void</span><span class="w"> </span><span class="nf">cgit_print_tag</span><span class="p">(</span><span class="kt">char</span><span class="w"> </span><span class="o">*</span><span class="n">revname</span><span class="p">);</span>

<span class="cp">#endif </span><span class="cm">/* UI_TAG_H */</span>
</pre></div>
</code></pre></td></tr></table>
</div> <!-- class=content -->
<div class='footer'>generated by <a href='https://git.zx2c4.com/cgit/about/'>cgit v1.2.3-54-g00ecf</a> (<a href='https://git-scm.com/'>git 2.39.0</a>) at 2025-03-16 11:45:32 +0000</div>
</div> <!-- id=cgit -->
</body>
</html>
ct cache_slot slot;
	char fullname[1024];
	char *name;

	if (!path) {
		cache_log("[cgit] cache path not specified\n");
		return -1;
	}
	if (strlen(path) > 1024 - 10) {
		cache_log("[cgit] cache path too long: %s\n",
			  path);
		return -1;
	}
	dir = opendir(path);
	if (!dir) {
		err = errno;
		cache_log("[cgit] unable to open path %s: %s (%d)\n",
			  path, strerror(err), err);
		return err;
	}
	strcpy(fullname, path);
	name = fullname + strlen(path);
	if (*(name - 1) != '/') {
		*name++ = '/';
		*name = '\0';
	}
	slot.cache_name = fullname;
	while((ent = readdir(dir)) != NULL) {
		if (strlen(ent->d_name) != 8)
			continue;
		strcpy(name, ent->d_name);
		if ((err = open_slot(&slot)) != 0) {
			cache_log("[cgit] unable to open path %s: %s (%d)\n",
				  fullname, strerror(err), err);
			continue;
		}
		printf("%s %s %10"PRIuMAX" %s\n",
		       name,
		       sprintftime("%Y-%m-%d %H:%M:%S",
				   slot.cache_st.st_mtime),
		       (uintmax_t)slot.cache_st.st_size,
		       slot.buf);
		close_slot(&slot);
	}
	closedir(dir);
	return 0;
}

/* Print a message to stdout */
void cache_log(const char *format, ...)
{
	va_list args;
	va_start(args, format);
	vfprintf(stderr, format, args);
	va_end(args);
}