From 0bc51d649418dd62629c888154a29d164818006c Mon Sep 17 00:00:00 2001
From: "carpentry-heartbeat[bot]"
 <carpentry-heartbeat[bot]@users.noreply.github.com>
Date: Sat, 20 Jun 2026 06:23:17 +0200
Subject: [PATCH] Fix blob column handling to preserve binary data with
 embedded nulls

Change Type.Blob from String to (Array Byte) so binary data with
embedded null bytes is not truncated. Add SQLiteColumn_from_blob to
return blob data as a length-aware Carp Array, and use the stored
blob_len in sqlite3_bind_blob instead of strlen.
---
 sqlite3.carp      |  9 ++++++---
 sqlite3_helper.h  | 20 +++++++++++++++-----
 test/sqlite3.carp | 16 +++++++++++++++-
 3 files changed, 36 insertions(+), 9 deletions(-)

diff --git a/sqlite3.carp b/sqlite3.carp
index fd150e1..c67109d 100644
--- a/sqlite3.carp
+++ b/sqlite3.carp
@@ -74,7 +74,7 @@ primitive Carp types can be casted to appropriate SQLite types by using the
     (Integer [Long])
     (Floating [Double])
     (Text [String])
-    (Blob [String]))
+    (Blob [(Array Byte)]))
 
   (private SQLiteColumn)
   (hidden SQLiteColumn)
@@ -86,7 +86,7 @@ primitive Carp types can be casted to appropriate SQLite types by using the
       (register int (Fn [Long] SQLiteColumn) "SQLiteColumn_int")
       (register float (Fn [Double] SQLiteColumn) "SQLiteColumn_float")
       (register text (Fn [String] SQLiteColumn) "SQLiteColumn_text")
-      (register blob (Fn [String] SQLiteColumn) "SQLiteColumn_blob"))
+      (register blob (Fn [(Array Byte)] SQLiteColumn) "SQLiteColumn_blob"))
 
     (defn = [a b]
       (match-ref a
@@ -114,6 +114,9 @@ primitive Carp types can be casted to appropriate SQLite types by using the
     (register from-integer (Fn [SQLiteColumn] Long) "SQLiteColumn_from_int")
     (register from-floating (Fn [SQLiteColumn] Double) "SQLiteColumn_from_float")
     (register from-text (Fn [SQLiteColumn] String) "SQLiteColumn_from_str")
+    (register from-blob
+      (Fn [SQLiteColumn] (Array Byte))
+      "SQLiteColumn_from_blob")
 
     (defn to-carp [c]
       (case (tag &c)
@@ -124,7 +127,7 @@ primitive Carp types can be casted to appropriate SQLite types by using the
             sql_text
             (Type.Text (from-text c))
             sql_blob
-            (Type.Blob (from-text c))
+            (Type.Blob (from-blob c))
             (Type.Null))))
 
   (private SQLiteRow)
diff --git a/sqlite3_helper.h b/sqlite3_helper.h
index 2be2d43..bb96920 100644
--- a/sqlite3_helper.h
+++ b/sqlite3_helper.h
@@ -8,6 +8,7 @@ typedef struct {
 
 typedef struct {
   int tag;
+  int blob_len;
   union {
     int64_t i;
     double f;
@@ -58,10 +59,19 @@ SQLiteColumn SQLiteColumn_text(char* s) {
   return res;
 }
 
-SQLiteColumn SQLiteColumn_blob(char* s) {
+SQLiteColumn SQLiteColumn_blob(Array a) {
   SQLiteColumn res;
   res.tag = SQLITE_BLOB;
-  res.s = s;
+  res.blob_len = a.len;
+  res.s = a.data;
+  return res;
+}
+
+Array SQLiteColumn_from_blob(SQLiteColumn col) {
+  Array res;
+  res.len = col.blob_len;
+  res.capacity = col.blob_len;
+  res.data = col.s;
   return res;
 }
 
@@ -183,9 +193,9 @@ const char* SQLite3_exec_internal(sqlite3_stmt* s, SQLiteRows* rows) {
           }
           case SQLITE_BLOB: {
             len = sqlite3_column_bytes(s, i);
-            c->s = CARP_MALLOC(len+1);
+            c->blob_len = len;
+            c->s = CARP_MALLOC(len);
             memcpy(c->s, sqlite3_column_blob(s, i), len);
-            c->s[len] = '\0';
             break;
           }
           case SQLITE_NULL:
@@ -239,7 +249,7 @@ const char* SQLite3_bind(sqlite3_stmt* s, Array* p) {
         res = sqlite3_bind_text(s, i+1, val.s, strlen(val.s), SQLITE_STATIC);
         break;
       case SQLITE_BLOB:
-        res = sqlite3_bind_blob(s, i+1, val.s, strlen(val.s), SQLITE_STATIC);
+        res = sqlite3_bind_blob(s, i+1, val.s, val.blob_len, SQLITE_STATIC);
         break;
     }
     if (res != SQLITE_OK) {
diff --git a/test/sqlite3.carp b/test/sqlite3.carp
index c5fcb6e..f803dea 100644
--- a/test/sqlite3.carp
+++ b/test/sqlite3.carp
@@ -289,4 +289,18 @@
       (let-do [r (SQLite3.query &db "SELECT * FROM t;" &[])]
         (SQLite3.close db)
         r))
-    "with-transaction rolls back on error"))
+    "with-transaction rolls back on error")
+
+  (assert-equal test
+    &(Result.Success [[(SQLite3.Type.Blob [0b 1b 0b 2b 3b])]])
+    &(let [db (open-memory)]
+      (let-do [r (do
+                 (ignore (SQLite3.query &db "CREATE TABLE t (data BLOB);" &[]))
+                 (ignore
+                   (SQLite3.query &db
+                                  "INSERT INTO t VALUES (?1);"
+                                  &[(SQLite3.Type.Blob [0b 1b 0b 2b 3b])]))
+                 (SQLite3.query &db "SELECT * FROM t;" &[]))]
+        (SQLite3.close db)
+        r))
+    "blob with embedded nulls round-trips correctly"))