From 6b0452b7227ca12853c672083ac68f52741beaee Mon Sep 17 00:00:00 2001
From: nishi <nishi@d4a5a174-5a4a-5b4b-b672-37683c10d7d5>
Date: Fri, 24 May 2024 03:06:42 +0000
Subject: [PATCH] delete_table works

git-svn-id: file:///raid/svn-main/nishi-dataworks/trunk@101 d4a5a174-5a4a-5b4b-b672-37683c10d7d5
---
 Library/database.c       |  2 +-
 Library/database_exec.c  | 26 ++++++++++++++++++++++++++
 Library/database_table.c | 32 ++++++++++++++++++++++++++++++++
 Library/dw_database.h    | 21 ++++++++++++++++++++-
 4 files changed, 79 insertions(+), 2 deletions(-)

diff --git a/Library/database.c b/Library/database.c
index 91fe598..a18cdd7 100644
--- a/Library/database.c
+++ b/Library/database.c
@@ -38,7 +38,7 @@
 
 const char sig[3] = {0x7f, 'D', 'W'};
 
-const char* dw_errors[] = {"Success", "Used already", "File open fail", "Invalid signature", "Invalid version", "Parser returned NULL", "Cannot call non-method", "Unknown method", "Insufficient arguments", "Too many arguments"};
+const char* dw_errors[] = {"Success", "Used already", "File open fail", "Invalid signature", "Invalid version", "Parser returned NULL", "Cannot call non-method", "Unknown method", "Insufficient arguments", "Too many arguments", "Not used"};
 
 #ifdef M_I86
 #define BUFSIZE 128
diff --git a/Library/database_exec.c b/Library/database_exec.c
index 73b4840..7d7ba7b 100644
--- a/Library/database_exec.c
+++ b/Library/database_exec.c
@@ -144,6 +144,29 @@ struct dataworks_db_result* __dataworks_database_execute_code(struct dataworks_d
 				free(fields);
 				free(fieldtypes);
 			}
+		} else if(__dw_strcaseequ(token->name, "delete_table")) {
+			argc = 0;
+			int j;
+			for(j = 0; results[j] != NULL; j++) {
+				if(results[j]->value != NULL) {
+					argc++;
+				}
+			}
+			if(argc < 1) {
+				r->error = true;
+				r->errnum = DW_ERR_EXEC_INSUFFICIENT_ARGUMENTS;
+			} else {
+				for(j = 0; results[j] != NULL; j++) {
+					if(results[j]->value != NULL) {
+						int er = dataworks_database_delete_table(db, results[j]->value);
+						if(er != DW_ERR_SUCCESS) {
+							r->error = true;
+							r->errnum = er;
+							break;
+						}
+					}
+				}
+			}
 		} else if(__dw_strcaseequ(token->name, "concat")) {
 			r->value = malloc(1);
 			r->value[0] = 0;
@@ -190,6 +213,9 @@ struct dataworks_db_result* __dataworks_database_execute_code(struct dataworks_d
 							if(dolog) {
 								printf("Using table `%s'.\n", db->name);
 							}
+						} else {
+							r->error = true;
+							r->errnum = DW_ERR_NOT_USED;
 						}
 					} else {
 						r->error = true;
diff --git a/Library/database_table.c b/Library/database_table.c
index cc9059b..2bb2ae9 100644
--- a/Library/database_table.c
+++ b/Library/database_table.c
@@ -34,6 +34,37 @@
 #include <stdlib.h>
 #include <string.h>
 
+int dataworks_database_delete_table(struct dataworks_db* db, const char* name) {
+	bool rm = false;
+	if(db->version == 1) {
+		__dw_lockfile(db->fp);
+		fseek(db->fp, 3 + 10, SEEK_SET);
+		int i;
+		struct dataworks_db_v1_indexentry index;
+		char* buf = malloc(1 + 8 + 1 + 256 + 4096);
+		for(i = 0; i < 256; i++) {
+			fread(buf, 1, 1 + 8 + 1 + 256 + 4096, db->fp);
+			__dw_buffer_to_db_v1_indexentry(buf, index);
+			if(index.flag & DATAWORKS_V1_INDEXENTRY_USED) {
+				char* dbname = malloc(index.dbname_len + 1);
+				memcpy(dbname, index.dbname, index.dbname_len);
+				dbname[index.dbname_len] = 0;
+				if(strcmp(dbname, name) == 0) {
+					fseek(db->fp, -(1 + 8 + 1 + 256 + 4096), SEEK_CUR);
+					buf[0] &= ~DATAWORKS_V1_INDEXENTRY_USED;
+					fwrite(buf, 1, 1 + 8 + 1 + 256 + 4096, db->fp);
+					rm = true;
+				}
+				free(dbname);
+			}
+		}
+		free(buf);
+		__dw_unlockfile(db->fp);
+	}
+	if(rm) return DW_ERR_SUCCESS;
+	return DW_ERR_NOT_USED;
+}
+
 int dataworks_database_create_table(struct dataworks_db* db, const char* name, char** fields, const char* fieldtypes) {
 	if(db->version == 1) {
 		__dw_lockfile(db->fp);
@@ -80,6 +111,7 @@ int dataworks_database_create_table(struct dataworks_db* db, const char* name, c
 		__dw_unlockfile(db->fp);
 		dataworks_database_update_mtime(db);
 	}
+	return DW_ERR_SUCCESS;
 }
 
 char** dataworks_database_get_table_list(struct dataworks_db* db) {
diff --git a/Library/dw_database.h b/Library/dw_database.h
index 7f2b43d..cd25f13 100644
--- a/Library/dw_database.h
+++ b/Library/dw_database.h
@@ -128,6 +128,13 @@ enum DW_ERRORS {
 	 *
 	 */
 	DW_ERR_EXEC_TOO_MANY_ARGUMENTS,
+
+	/**
+	 * @~english
+	 * @brief Not used
+	 *
+	 */
+	DW_ERR_NOT_USED,
 };
 
 /**
@@ -322,12 +329,24 @@ char** dataworks_database_get_table_list(struct dataworks_db* db);
  * @param fields Fields
  * @param fieldtypes Types
  * @return
- * - `0` if success
+ * - `DW_ERR_SUCCESS` if success
  * - `DW_ERR_USED` if the name is already used
  *
  */
 int dataworks_database_create_table(struct dataworks_db* db, const char* name, char** fields, const char* fieldtypes);
 
+/**
+ * @~english
+ * @brief Deletes a table.
+ * @param db Database
+ * @param name Table name
+ * @return
+ * - `DW_ERR_SUCCESS` if success
+ * - `DW_ERR_NOT_USED` if the name is not used
+ *
+ */
+int dataworks_database_delete_table(struct dataworks_db* db, const char* name);
+
 /**
  * @~english
  * @brief Converts error number to a string.
-- 
2.43.0