test: add aaruf_identify and aaruf_identify_stream tests

15 tests covering the image identification API:

- Happy path: valid V1 and V2 images via both file path and stream
- Error handling: NULL stream, empty file, truncated header
- Format validation: wrong magic bytes, future version, legacy DIC_MAGIC
- Stream behavior: mid-position seek-to-zero before reading
- File path errors: non-existent path, non-Aaru file, NULL path

Uses existing V1/V2 .aif fixtures from tests/data/ plus crafted
in-memory headers via tmpfile() for edge cases.

tests/CMakeLists.txt

@@ -91,6 +91,7 @@ add_executable(tests_run
     open_image.cpp
     create_image.cpp
     verify_image.cpp
+    identify.cpp
     ps3_aes.cpp
     ps3_crypto.cpp
     ps3_encryption_map.cpp

tests/identify.cpp

@@ -0,0 +1,188 @@
+/*
+ * This file is part of the Aaru Data Preservation Suite.
+ * Copyright (c) 2019-2026 Natalia Portillo.
+ *
+ * This library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of the
+ * License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <cerrno>
+#include <climits>
+#include <cstdint>
+#include <cstdio>
+#include <cstring>
+
+#include "../include/aaruformat.h"
+#include "gtest/gtest.h"
+
+// Helper: create a tmpfile containing a crafted AaruHeader with the given magic and version.
+// Returns the FILE* rewound to position 0. Caller must fclose().
+static FILE *make_header_stream(uint64_t magic, uint8_t major_version)
+{
+    FILE *f = tmpfile();
+    EXPECT_NE(f, nullptr);
+    if(f == nullptr) return nullptr;
+
+    AaruHeader hdr;
+    memset(&hdr, 0, sizeof(hdr));
+    hdr.identifier       = magic;
+    hdr.imageMajorVersion = major_version;
+    fwrite(&hdr, sizeof(hdr), 1, f);
+    rewind(f);
+    return f;
+}
+
+class IdentifyFixture : public testing::Test
+{
+public:
+    IdentifyFixture() = default;
+
+protected:
+    char path[PATH_MAX];
+    char filename[PATH_MAX];
+
+    void SetUp() override { getcwd(path, PATH_MAX); }
+};
+
+// ---------------------------------------------------------------------------
+// aaruf_identify_stream() tests
+// ---------------------------------------------------------------------------
+
+TEST_F(IdentifyFixture, StreamValidV2)
+{
+    snprintf(filename, PATH_MAX, "%s/data/mf2hd.aif", path);
+    FILE *f = fopen(filename, "rb");
+    ASSERT_NE(f, nullptr) << "Failed to open mf2hd.aif";
+
+    EXPECT_EQ(aaruf_identify_stream(f), 100);
+    fclose(f);
+}
+
+TEST_F(IdentifyFixture, StreamValidV1)
+{
+    snprintf(filename, PATH_MAX, "%s/data/mf2hd_v1.aif", path);
+    FILE *f = fopen(filename, "rb");
+    ASSERT_NE(f, nullptr) << "Failed to open mf2hd_v1.aif";
+
+    EXPECT_EQ(aaruf_identify_stream(f), 100);
+    fclose(f);
+}
+
+TEST_F(IdentifyFixture, StreamNull)
+{
+    EXPECT_EQ(aaruf_identify_stream(nullptr), 0);
+}
+
+TEST_F(IdentifyFixture, StreamNonAaru)
+{
+    snprintf(filename, PATH_MAX, "%s/data/random", path);
+    FILE *f = fopen(filename, "rb");
+    ASSERT_NE(f, nullptr) << "Failed to open random data file";
+
+    EXPECT_EQ(aaruf_identify_stream(f), 0);
+    fclose(f);
+}
+
+TEST_F(IdentifyFixture, StreamEmptyFile)
+{
+    FILE *f = tmpfile();
+    ASSERT_NE(f, nullptr);
+
+    EXPECT_EQ(aaruf_identify_stream(f), 0);
+    fclose(f);
+}
+
+TEST_F(IdentifyFixture, StreamTruncatedHeader)
+{
+    // Write only the 8-byte magic — not enough for a full AaruHeader (104 bytes)
+    FILE *f = tmpfile();
+    ASSERT_NE(f, nullptr);
+
+    const uint64_t magic = AARU_MAGIC;
+    fwrite(&magic, sizeof(magic), 1, f);
+    rewind(f);
+
+    EXPECT_EQ(aaruf_identify_stream(f), 0);
+    fclose(f);
+}
+
+TEST_F(IdentifyFixture, StreamInvalidMagic)
+{
+    FILE *f = make_header_stream(0xDEADBEEFDEADBEEFULL, 2);
+    ASSERT_NE(f, nullptr);
+
+    EXPECT_EQ(aaruf_identify_stream(f), 0);
+    fclose(f);
+}
+
+TEST_F(IdentifyFixture, StreamFutureVersion)
+{
+    FILE *f = make_header_stream(AARU_MAGIC, 255);
+    ASSERT_NE(f, nullptr);
+
+    EXPECT_EQ(aaruf_identify_stream(f), 0);
+    fclose(f);
+}
+
+TEST_F(IdentifyFixture, StreamDicMagic)
+{
+    FILE *f = make_header_stream(DIC_MAGIC, 1);
+    ASSERT_NE(f, nullptr);
+
+    EXPECT_EQ(aaruf_identify_stream(f), 100);
+    fclose(f);
+}
+
+TEST_F(IdentifyFixture, StreamMidPosition)
+{
+    // Verify identify_stream seeks to 0 even when stream is positioned elsewhere
+    snprintf(filename, PATH_MAX, "%s/data/mf2hd.aif", path);
+    FILE *f = fopen(filename, "rb");
+    ASSERT_NE(f, nullptr) << "Failed to open mf2hd.aif";
+
+    fseek(f, 50, SEEK_SET);
+    EXPECT_EQ(aaruf_identify_stream(f), 100);
+    fclose(f);
+}
+
+// ---------------------------------------------------------------------------
+// aaruf_identify() tests
+// ---------------------------------------------------------------------------
+
+TEST_F(IdentifyFixture, FileValidV2)
+{
+    snprintf(filename, PATH_MAX, "%s/data/mf2hd.aif", path);
+    EXPECT_EQ(aaruf_identify(filename), 100);
+}
+
+TEST_F(IdentifyFixture, FileValidV1)
+{
+    snprintf(filename, PATH_MAX, "%s/data/mf2hd_v1.aif", path);
+    EXPECT_EQ(aaruf_identify(filename), 100);
+}
+
+TEST_F(IdentifyFixture, FileNull)
+{
+    EXPECT_EQ(aaruf_identify(nullptr), EINVAL);
+}
+
+TEST_F(IdentifyFixture, FileNonExistent)
+{
+    EXPECT_EQ(aaruf_identify("/tmp/aaruf_test_nonexistent_identify.aif"), ENOENT);
+}
+
+TEST_F(IdentifyFixture, FileNonAaru)
+{
+    snprintf(filename, PATH_MAX, "%s/data/random", path);
+    EXPECT_EQ(aaruf_identify(filename), 0);
+}