Changeset 80425

Timestamp:

07/12/11 10:21:45 (4 years ago)

Author:

cal@…

Message:

rev-upgrade: Added hashmap to libmachista to prevent unnecessary I/O

Location:

branches/gsoc11-rev-upgrade/base/src/libmachista1.0

Files:

• Makefile (modified) (1 diff)
• hashmap.c (added)
• hashmap.h (added)
• libmachista.c (modified) (6 diffs)
• libmachista.h (modified) (1 diff)

branches/gsoc11-rev-upgrade/base/src/libmachista1.0/Makefile

@@ -1 @@
-OBJS=           libmachista.o
+OBJS=           libmachista.o hashmap.o
 SHLIB_NAME=     libmachista${SHLIB_SUFFIX}
 INSTALLDIR=     ${DESTDIR}${datadir}/macports/Tcl/libmachista1.0

branches/gsoc11-rev-upgrade/base/src/libmachista1.0/libmachista.c

@@ -49 +49 @@
 
 #include "libmachista.h"
+#include "hashmap.h"
 
 typedef struct macho_input {
@@ -57 +58 @@
 /* This is macho_handle_t. The corresponding typedef is in the header */
 struct macho_handle {
-    /* this isn't handled as a linked list on purpose, because the mht_results are given out to the
-     * user and should not have a next pointer (as it doesn't make any sense in that context */
-    size_t mht_result_count;
-    macho_t **mht_results;
+    HashMap *result_map;
 };
 
@@ -399 +397 @@
 
 /* Parse a (possible Mach-O) file. For a more detailed description, see the header */
-int macho_parse_file(macho_handle_t *handle, const char *filepath, macho_t **res) {
+int macho_parse_file(macho_handle_t *handle, const char *filepath, const macho_t **res) {
     int fd;
     struct stat st;
     void *data;
     macho_input_t input_file;
+
+    /* Check hashmap for precomputed results */
+    const macho_t *cached_res = hashMapGet(handle->result_map, filepath);
+    if (cached_res != NULL) {
+        *res = cached_res;
+        return MACHO_SUCCESS;
+    }
+
     
     /* Open input file */
@@ -430 +436 @@
         return MACHO_EMEM;
 
-    int ret = parse_macho(*res, &input_file);
+    /* The output parameter *res should be read-only for the user of the lib only, but writable for
+     * us */
+    int ret = parse_macho((macho_t *)*res, &input_file);
     if (ret == MACHO_SUCCESS) {
-        /* TODO: Insert into hashmap for caching */
-        macho_t **handle_list = realloc(handle->mht_results, (handle->mht_result_count + 1) * sizeof(*handle->mht_results));
-        if (handle_list == NULL) {
-            free_macho_t(*res);
+        /* Insert into hashmap for caching */
+        if (0 == hashMapPut(handle->result_map, filepath, *res, NULL)) {
+            free_macho_t((macho_t *)*res);
             *res = NULL;
             ret = MACHO_EMEM;
-        } else {
-            handle->mht_results = handle_list;
-            handle->mht_result_count++;
-            handle->mht_results[handle->mht_result_count - 1] = *res;
         }
     } else {
         /* An error occured, free mt */
-        free_macho_t(*res);
+        free_macho_t((macho_t *)*res);
         *res = NULL;
     }
@@ -461 +464 @@
     if (mht == NULL)
         return NULL;
-    memset(mht, 0, sizeof(mht));
+    mht->result_map = hashMapCreate((void (*)(const void *))free_macho_t);
+    if (mht->result_map == NULL) {
+        free(mht);
+        return NULL;
+    }
     return mht;
 }
@@ -470 +477 @@
         return;
     
-    for (size_t i = 0; i < handle->mht_result_count; ++i)
-        free_macho_t(handle->mht_results[i]);
-    free(handle->mht_results);
+    hashMapDestroy(handle->result_map);
 
     free(handle);

branches/gsoc11-rev-upgrade/base/src/libmachista1.0/libmachista.h

@@ -125 +125 @@
  * On error, the contents of res are undefined and should not be used. The memory associated with
  * the result *res will be free()'d and should thus not be used after calling macho_destroy_handle
- * on the macho_handle_t used for the call.
+ * on the macho_handle_t used for the call. *res should also never be modified or otherwise
+ * free()'d.
  */
-int macho_parse_file(macho_handle_t *handle, const char *filepath, macho_t **res);
+int macho_parse_file(macho_handle_t *handle, const char *filepath, const macho_t **res);
 
 /**