From ba26575890dcb3a5244a337a4e4758c01b9aca9b Mon Sep 17 00:00:00 2001
From: Allanis <allanis@saracraft.net>
Date: Sat, 26 Apr 2014 19:47:10 +0100
Subject: [PATCH] [Add] Started to work on cacheing the packfile.
---
src/pack.c | 240 +++++++++++++++++++++++++++++++++++++++++------------
src/pack.h | 10 +++
2 files changed, 198 insertions(+), 52 deletions(-)
diff --git a/src/pack.c b/src/pack.c
index e1b2a48..3d2581c 100644
--- a/src/pack.c
+++ b/src/pack.c
@@ -33,8 +33,6 @@
*/
/**
- * @struct Packfile
- *
* @brief Abstracts around packfiles.
*/
struct Packfile_s {
@@ -46,8 +44,36 @@ struct Packfile_s {
uint32_t pos; /**< Cursor position. */
uint32_t start; /**< File start. */
uint32_t end; /**< File end. */
+
+ uint32_t flags; /**< Special control flags. */
};
+/**
+ * @brief Allows much faster creation of packfiles.
+ */
+struct Packcache_s {
+#ifdef _POSIX_SOURCE
+ int fd; /**< File descriptor. */
+#else
+ FILE* fp; /* For non-posix. */
+#endif
+
+ char** index; /**< Cached index for faster lookups. */
+ uint32_t* start; /**< Cached index starts. */
+ uint32_t* nindex; /**< Number of index entries. */
+};
+
+/* Helper defines. */
+#ifdef _POSIX_SOURCE
+#define READ(f, b, n) if(read((f)->fd, (b), (n)) != (n)) { \
+ ERR("Fewer bytes read then expected"); \
+ return NULL; }
+#else
+#define READ(f, b, n) if(fread((b), 1, (n),(f)->fp) != (n)) { \
+ ERR("Fewer bytes read then expected"); \
+ return NULL; }
+#endif
+
#undef DEBUG /* This will be spammy. */
#define DEBUG(str, args...) do{;} while(0)
@@ -62,9 +88,142 @@ struct Packfile_s {
const uint64_t magic = 0x25524573; /**< File magic number: sER% */
+/* Flags. */
+#define PACKFILE_FROMCACHE (1<<0) /**< Packfile comes from a packcache. */
+
+static off_t getfilesize(const char* filename);
+
+/**
+ * @brief Open a packfile as a cache.
+ * @param packfile Name of the packfile to cache.
+ * @return NULL if an error occured or the Packcache.
+ */
+Packcache_t* pack_openCache(const char* packfile) {
+ int j;
+ uint32_t i;
+ char buf[PATH_MAX];
+ Packcache_t* cache;
+
+ /* Allocate memory. */
+ cache = calloc(1, sizeof(Packcache_t));
+ if(cache == NULL) {
+ ERR("Out of memory.");
+ return NULL;
+ }
+
+ /* Open file. */
+#ifdef _POSIX_SOURCE
+ cache->fd = open(packfile, O_RDONLY);
+ if(cache->fd == -1) {
+#else
+ cache->fp = fopen(packfile, "rb");
+ if(cache->fp == NULL) {
+#endif
+ ERR("Error opening %s: %s", packfile, strerror(errno));
+ return NULL;
+ }
+ /* Check for validity. */
+ READ(cache, buf, sizeof(magic));
+ if(memcmp(buf, &magic, sizeof(magic))) {
+ ERR("File %s is not a valid packfile", packfile);
+ return NULL;
+ }
+
+ /* Get the number of files and allocate memory. */
+ READ(cache, &cache->nindex, 4);
+ cache->index = calloc(cache->nindex, sizeof(char*));
+ cache->start = calloc(cache->nindex, sizeof(uint32_t));
+
+ /* Read index. */
+ for(i = 0; i < cache->nindex; i++) { /* Start to search files. */
+ j = 0;
+ READ(cache, &buf[j], 1); /* Get the name. */
+ while(buf[j++] != '\0')
+ READ(cache, &buf[j], 1);
+
+ cache->index[i] = strdup(buf);
+ READ(cache, &cache->start[i], 4);
+ DEBUG("'%s' found at %d", filename, cache->start[i]);
+ break;
+ }
+ /* Return the built cache. */
+ return cache;
+}
+
+/**
+ * @brief Close a Packcache.
+ * @param cache Packcache to close.
+ */
+void pack_closeCache(Packcache_t* cache) {
+ uint32_t i;
+
+ /* Close file. */
+#ifdef _POSIX_SOURCE
+ close(cache->fd);
+#else
+ fclose(cache->fp);
+#endif
+
+ /* Free memory. */
+ if(cache->nindex > 0) {
+ for(i = 0; i < cache->nindex; i++)
+ free(cache->index[i]);
+ free(cache->index);
+ free(cache->start);
+ }
+}
+
+/**
+ * @brief Open a packfile from a Packcache.
+ * @param cache Packcache to create Packfile from.
+ * @param filename Name of the file to open in the Cache.
+ * @return A packfile for filename from cache.
+ */
+Packfile_t* pack_openFromCache(Packcache_t* cache, const char* filename) {
+ uint32_t i;
+ Packfile_t* file;
+
+ file = calloc(1, sizeof(Packfile_t));
+
+ for(i = 0; i < cache->nindex; i++) {
+ if(strcmp(cache->index[i], filename)==0) {
+ /* Copy file. */
+#ifdef _POSIX_SOURCE
+ file->fd = dup(cache->fd);
+#else
+ file->fp = cache->fp;
+#endif
+
+ /* Copy information. */
+ file->flags |= PACKFILE_FROMCACHE;
+ file->start = cache->start[i];
+
+ /* Seek. */
+ if(file->start) { /* Go to the beginning of the file. */
+#ifdef _POSIX_SOURCE
+ if((uint32_t)lseek(file->fd, file->start, SEEK_SET) != file->start) {
+#else
+ fseek(file->fp, file->start, SEEK_SET);
+ if(errno) {
+#endif
+ ERR("Failure to seek to file start: %s", strerror(errno));
+ return NULL;
+ }
+
+ READ(file, &file->end, 4);
+ DEBUG("\t%d bytes", file->end);
+ file->pos = file->start;
+ file->end += file->start;
+ }
+
+ break;
+ }
+ }
+
+ return NULL;
+}
+
/**
- * @fn static off_t getfilesize(const char* filename)
- *
* @brief Get the file size.
* @param filename File to get the size of.
* @return The size of the file.
@@ -269,15 +428,6 @@ int pack_files(const char* outfile, const char** infiles, const uint32_t nfiles)
}
#undef WRITE
-#ifdef _POSIX_SOURCE
-#define READ(b,n) if(read(file->fd, (b), (n))!=(n)) { \
- ERR("Fewer bytes read than expected."); \
- free(buf); return NULL; }
-#else
-#define READ(b,n) if(fread((b), 1, (n), file->fp)!=(n)) { \
- ERR("Fewer bytes read then expected"); \
- free(buf); return NULL; }
-#endif
/**
* @brief Open a file in the packfile for reading.
* @param file Packfile to store data into.
@@ -288,13 +438,12 @@ int pack_files(const char* outfile, const char** infiles, const uint32_t nfiles)
Packfile_t* pack_open(const char* packfile, const char* filename) {
int j;
uint32_t nfiles, i;
- char* buf = malloc(PATH_MAX);
+ char buf[PATH_MAX];
Packfile_t* file;
/* Allocate memory. */
file = malloc(sizeof(Packfile_t));
memset(file, 0, sizeof(Packfile_t));
- buf = malloc(PATH_MAX);
#ifdef _POSIX_SOURCE
file->fd = open(packfile, O_RDONLY);
@@ -307,23 +456,23 @@ Packfile_t* pack_open(const char* packfile, const char* filename) {
return NULL;
}
- READ(buf, sizeof(magic)); /* Make sure it's a packfile. */
+ READ(file, buf, sizeof(magic)); /* Make sure it's a packfile. */
if(memcmp(buf, &magic, sizeof(magic))) {
ERR("File %s is not a valid packfile", filename);
return NULL;
}
- READ(&nfiles, 4);
+ READ(file, &nfiles, 4);
for(i = 0; i < nfiles; i++) {
/* Start to search files. */
j = 0;
- READ(&buf[j], 1); /* Get the name. */
+ READ(file, &buf[j], 1); /* Get the name. */
while(buf[j++] != '\0')
- READ(&buf[j], 1);
+ READ(file, &buf[j], 1);
if(strcmp(filename, buf) == 0) {
/* We found the file. */
- READ(&file->start, 4);
+ READ(file, &file->start, 4);
DEBUG("'%s' found at %d", filename, file->start);
break;
}
@@ -333,7 +482,6 @@ Packfile_t* pack_open(const char* packfile, const char* filename) {
fseek(file->fp, 4, SEEK_CUR);
#endif
}
- free(buf);
if(file->start) {
/* Go to the beginning of the file. */
@@ -346,7 +494,7 @@ Packfile_t* pack_open(const char* packfile, const char* filename) {
ERR("Failure to seek to file start: %s", strerror(errno));
return NULL;
}
- READ(&file->end, 4);
+ READ(file, &file->end, 4);
DEBUG("\t%d bytes", file->end);
file->pos = file->start;
file->end += file->start;
@@ -356,7 +504,6 @@ Packfile_t* pack_open(const char* packfile, const char* filename) {
}
return file;
}
-#undef READ
/**
* @brief Reads data from a packfile.
@@ -368,12 +515,12 @@ Packfile_t* pack_open(const char* packfile, const char* filename) {
* @return Bytes to read or -1 on error.
*/
ssize_t pack_read(Packfile_t* file, void* buf, size_t count) {
+ int bytes;
+
if(file->pos + count > file->end)
count = file->end - file->pos; /* Can't go past the end! */
if(count == 0) return 0;
- int bytes;
-
#ifdef _POSIX_SOURCE
if((bytes = read(file->fd, buf, count)) == -1) {
#else
@@ -538,66 +685,52 @@ void* pack_readfile(const char* packfile, const char* filename, uint32_t* filesi
* @param nfiles Stores the amount of files in packfile.
* @return An array of filenames in packfile.
*/
-#ifdef _POSIX_SOURCE
-#define READ(b,n) if(read(fd, (b), (n))!=(n)) { \
- ERR("Too few bytes read"); \
- return NULL; }
-#else
-#define READ(b,n) if(fread((b), 1, (n), fp) != (n)) { \
- ERR("Too few bytes read"); \
- return NULL; }
-#endif
char** pack_listfiles(const char* packfile, uint32_t* nfiles) {
-#ifdef _POSIX_SOURCE
- int fd;
-#else
- FILE* fp;
-#endif
int j;
uint32_t i;
+ Packfile_t file;
char** filenames;
char* buf = malloc(sizeof(magic));
*nfiles = 0;
#ifdef _POSIX_SOURCE
- fd = open(packfile, O_RDONLY);
- if(fd == -1) {
+ file.fd = open(packfile, O_RDONLY);
+ if(file.fd == -1) {
#else
- fp = fopen(packfile, "rb");
- if(fp == NULL) {
+ file.fp = fopen(packfile, "rb");
+ if(file.fp == NULL) {
#endif
ERR("opening %s: %s", packfile, strerror(errno));
return NULL;
}
- READ(buf, sizeof(magic)); /* Make sure it is a packfile. */
+ READ(&file, buf, sizeof(magic)); /* Make sure it's a packfile. */
if(memcmp(buf, &magic, sizeof(magic))) {
ERR("File %s is not a valid packfile", packfile);
return NULL;
}
- READ(nfiles, 4);
+ READ(&file, nfiles, 4);
filenames = malloc(((*nfiles)+1)*sizeof(char*));
for(i = 0; i < *nfiles; i++) {
/* Start searching files. */
j = 0;
filenames[i] = malloc(PATH_MAX * sizeof(char));
- READ(&filenames[i][j], 1); /* Get the name. */
+ READ(&file, &filenames[i][j], 1); /* Get the name. */
while(filenames[i][j++] != '\0')
- READ(&filenames[i][j], 1);
- READ(buf, 4); /* skip the location. */
+ READ(&file, &filenames[i][j], 1);
+ READ(&file, buf, 4); /* skip the location. */
}
free(buf);
#ifdef _POSIX_SOURCE
- close(fd);
+ close(file.fd);
#else
- fclose(fp);
+ fclose(file.fp);
#endif
return filenames;
}
-#undef READ
/**
* @brief Closes a packfile.
@@ -609,7 +742,10 @@ int pack_close(Packfile_t* file) {
#ifdef _POSIX_SOURCE
i = close(file->fd);
#else
- i = fclose(file->fp);
+ if(file->flags & PACKFILE_FROMCACHE)
+ i = 0;
+ else
+ i = fclose(file->fp);
#endif
return (i) ? -1 : 0;
}
diff --git a/src/pack.h b/src/pack.h
index 2be5f36..22e7372 100644
--- a/src/pack.h
+++ b/src/pack.h
@@ -9,6 +9,16 @@
struct Packfile_s;
typedef struct Packfile_s Packfile_t;
+struct Packcache_s;
+typedef struct Packcache_s Packcache_t;
+
+/*
+ * Packcache manipulation.
+ */
+Packcache_t* pack_openCache(const char* packfile);
+void pack_closeCache(Packcache_t* cache);
+Packfile_t* pack_openFromCache(Packcache_t* cache, const char* filename);
+
/* Packfile manipulation. Automatically allocated and freed (with open and close). */
/* Basic. */