From 1c79c56d617dee3a70e848d7ba437a69ef0330db Mon Sep 17 00:00:00 2001
From: avsdev-cw <craig@avsdev.uk>
Date: Thu, 8 Oct 2020 10:21:17 +0100
Subject: [PATCH] Convenience functions for moving/copying column data strings
 & blobs

---
 src/modb_accounting_p.c | 13 ++++++-----
 src/modb_p.c            | 50 +++++++++++++++++++++++++++++++++++++++++
 src/modb_p.h            |  5 +++++
 3 files changed, 62 insertions(+), 6 deletions(-)

diff --git a/src/modb_accounting_p.c b/src/modb_accounting_p.c
index e82a24d..c32550c 100644
--- a/src/modb_accounting_p.c
+++ b/src/modb_accounting_p.c
@@ -42,13 +42,13 @@ int tableRowsToUsers(column_data **col_data, size_t n_cols,
     }
 
     user->id = *(col_id->data.ptr_uint32 + idx);
-    if (strmemcpy(*(col_username->data.ptr_str + idx), *(col_username->data_lens + idx),
-                  &user->username, &user->username_len) != 0) {
+
+    if (!moveColumnStrPointer(col_username, idx, 1, &user->username, &user->username_len)) {
       freeUsers(users, idx);
       return -1;
     }
-    if (strmemcpy(*(col_email->data.ptr_str + idx), *(col_email->data_lens + idx),
-                  &user->email, &user->email_len) != 0) {
+
+    if (!moveColumnStrPointer(col_email, idx, 1, &user->email, &user->email_len)) {
       freeUsers(users, idx);
       return -1;
     }
@@ -177,11 +177,12 @@ int tableRowsToGroups(column_data **col_data, size_t n_cols,
     }
 
     group->id = *(col_id->data.ptr_uint32 + idx);
-    if (strmemcpy(*(col_name->data.ptr_str + idx), *(col_name->data_lens + idx),
-                  &group->name, &group->name_len) != 0) {
+
+    if (!moveColumnStrPointer(col_name, idx, 1, &group->name, &group->name_len)) {
       freeGroups(groups, idx);
       return -1;
     }
+
     group->created_on = *(col_created->data.ptr_uint32 + idx);
     if (!columnRowIsNull(col_updated, idx)) {
       group->updated_on = *(col_updated->data.ptr_uint32 + idx);
diff --git a/src/modb_p.c b/src/modb_p.c
index b44542a..173a29b 100644
--- a/src/modb_p.c
+++ b/src/modb_p.c
@@ -1,3 +1,7 @@
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+
 #include "modb_p.h"
 #include "strext.h"
 
@@ -144,3 +148,49 @@ void modbColumnNameAs_sb(str_builder *sb, modb_ref *modb,
   strbld_str(sb, as_column, as_column_len);
   strbld_char(sb, '`');
 }
+
+
+int moveColumnStrPointer(column_data *col, size_t row, int move, char **target, size_t *target_len)
+{
+  if (columnRowIsNull(col, row)) {
+    return 0;
+  }
+
+  if (move) {
+    *target = *(col->data.ptr_str + row);
+    *(col->data.ptr_str + row) = 0;
+    *target_len = *(col->data_lens + row);
+    *(col->data_lens + row) = 0;
+  } else {
+    if (strmemcpy(*(col->data.ptr_str + row), *(col->data_lens + row), target, target_len) != 0) {
+      return -1;
+    }
+  }
+
+  return 0;
+}
+int moveColumnBlobPointer(column_data *col, size_t row, int move,
+                          char **target, size_t *target_len)
+{
+  if (columnRowIsNull(col, row)) {
+    return 0;
+  }
+
+  if (move) {
+    *target = *(col->data.ptr_blob + row);
+    *(col->data.ptr_blob + row) = 0;
+    *target_len = *(col->data_lens + row);
+    *(col->data_lens + row) = 0;
+  } else {
+    *target = (char *)malloc(*(col->data_lens + row));
+    if (*target == 0) {
+      fprintf(stderr, "[%d]malloc: (%d) %s\n", __LINE__, errno, strerror(errno));
+      return -1;
+    }
+
+    memcpy(*target, *(col->data.ptr_blob + row), *(col->data_lens + row));
+    *target_len = *(col->data_lens + row);
+  }
+
+  return 0;
+}
diff --git a/src/modb_p.h b/src/modb_p.h
index ae87e9a..51e8d44 100644
--- a/src/modb_p.h
+++ b/src/modb_p.h
@@ -4,6 +4,7 @@
 #include <stddef.h>
 
 #include "modb_types.h"
+#include "database.h"
 #include "strext.h"
 
 
@@ -48,5 +49,9 @@ void modbColumnNameAs_sb(str_builder *sb, modb_ref *modb,
                          const char *column, size_t column_len,
                          const char *as_column, size_t as_column_len);
 
+int moveColumnStrPointer(column_data *col, size_t row, int move, char **target, size_t *target_len);
+int moveColumnBlobPointer(column_data *col, size_t row, int move,
+                          char **target, size_t *target_len);
+
 
 #endif // H__MODB_P__