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Merged
merged 1 commit into from
Mar 5, 2022
Merged

Allow NULL buffers with 0 length to be used #97

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30 changes: 17 additions & 13 deletions src/mpack/mpack-writer.c
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Original file line number Diff line number Diff line change
Expand Up @@ -1246,7 +1246,7 @@ void mpack_start_ext(mpack_writer_t* writer, int8_t exttype, uint32_t count) {
*/

void mpack_write_str(mpack_writer_t* writer, const char* data, uint32_t count) {
mpack_assert(data != NULL, "data for string of length %i is NULL", (int)count);
mpack_assert(count == 0 || data != NULL, "data for string of length %i is NULL", (int)count);

#if MPACK_OPTIMIZE_FOR_SIZE
mpack_writer_track_element(writer);
Expand Down Expand Up @@ -1301,7 +1301,7 @@ void mpack_write_str(mpack_writer_t* writer, const char* data, uint32_t count) {
}

void mpack_write_bin(mpack_writer_t* writer, const char* data, uint32_t count) {
mpack_assert(data != NULL, "data pointer for bin of %i bytes is NULL", (int)count);
mpack_assert(count == 0 || data != NULL, "data pointer for bin of %i bytes is NULL", (int)count);
mpack_start_bin(writer, count);
mpack_write_bytes(writer, data, count);
mpack_finish_bin(writer);
Expand All @@ -1317,16 +1317,18 @@ void mpack_write_ext(mpack_writer_t* writer, int8_t exttype, const char* data, u
#endif

void mpack_write_bytes(mpack_writer_t* writer, const char* data, size_t count) {
mpack_assert(data != NULL, "data pointer for %i bytes is NULL", (int)count);
mpack_assert(count == 0 || data != NULL, "data pointer for %i bytes is NULL", (int)count);
mpack_writer_track_bytes(writer, count);
mpack_write_native(writer, data, count);
}

void mpack_write_cstr(mpack_writer_t* writer, const char* cstr) {
mpack_assert(cstr != NULL, "cstr pointer is NULL");
size_t length = mpack_strlen(cstr);
if (length > MPACK_UINT32_MAX)
mpack_writer_flag_error(writer, mpack_error_invalid);
size_t length = 0;
if (cstr) {
length = mpack_strlen(cstr);
if (length > MPACK_UINT32_MAX)
mpack_writer_flag_error(writer, mpack_error_invalid);
}
mpack_write_str(writer, cstr, (uint32_t)length);
}

Expand All @@ -1338,7 +1340,7 @@ void mpack_write_cstr_or_nil(mpack_writer_t* writer, const char* cstr) {
}

void mpack_write_utf8(mpack_writer_t* writer, const char* str, uint32_t length) {
mpack_assert(str != NULL, "data for string of length %i is NULL", (int)length);
mpack_assert(length == 0 || str != NULL, "data for string of length %i is NULL", (int)length);
if (!mpack_utf8_check(str, length)) {
mpack_writer_flag_error(writer, mpack_error_invalid);
return;
Expand All @@ -1347,11 +1349,13 @@ void mpack_write_utf8(mpack_writer_t* writer, const char* str, uint32_t length)
}

void mpack_write_utf8_cstr(mpack_writer_t* writer, const char* cstr) {
mpack_assert(cstr != NULL, "cstr pointer is NULL");
size_t length = mpack_strlen(cstr);
if (length > MPACK_UINT32_MAX) {
mpack_writer_flag_error(writer, mpack_error_invalid);
return;
size_t length = 0;
if (cstr) {
length = mpack_strlen(cstr);
if (length > MPACK_UINT32_MAX) {
mpack_writer_flag_error(writer, mpack_error_invalid);
return;
}
}
mpack_write_utf8(writer, cstr, (uint32_t)length);
}
Expand Down
55 changes: 55 additions & 0 deletions test/unit/src/test-write.c
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Original file line number Diff line number Diff line change
Expand Up @@ -1005,6 +1005,7 @@ static void test_write_utf8(void) {
// these test strings are mostly duplicated from test-expect.c, but
// without the MessagePack header

const char empty_string[] = "\x00";
const char utf8_null[] = "hello\x00world";
const char utf8_valid[] = " \xCF\x80 \xe4\xb8\xad \xf0\xa0\x80\xb6";
const char utf8_trimmed[] = "\xf0\xa0\x80\xb6";
Expand All @@ -1016,6 +1017,11 @@ static void test_write_utf8(void) {
const char utf8_cesu8[] = " \xED\xA0\x81\xED\xB0\x80 ";
const char utf8_wobbly[] = " \xED\xA0\x81 ";

// An empty string should be written successfully
TEST_SIMPLE_WRITE_NOERROR(mpack_write_str(&writer, utf8_null, 0));
TEST_SIMPLE_WRITE_NOERROR(mpack_write_str(&writer, NULL, 0));
TEST_SIMPLE_WRITE_NOERROR(mpack_write_str(&writer, empty_string, 0));

// all non-UTF-8 writers should write these strings without error
TEST_SIMPLE_WRITE_NOERROR(mpack_write_str(&writer, utf8_null, (uint32_t)sizeof(utf8_null)-1));
TEST_SIMPLE_WRITE_NOERROR(mpack_write_str(&writer, utf8_valid, (uint32_t)sizeof(utf8_valid)-1));
Expand All @@ -1027,6 +1033,10 @@ static void test_write_utf8(void) {
TEST_SIMPLE_WRITE_NOERROR(mpack_write_str(&writer, utf8_cesu8, (uint32_t)sizeof(utf8_cesu8)-1));
TEST_SIMPLE_WRITE_NOERROR(mpack_write_str(&writer, utf8_wobbly, (uint32_t)sizeof(utf8_wobbly)-1));

// A NULL string or string with 0 length should be accepted
TEST_SIMPLE_WRITE_NOERROR(mpack_write_cstr(&writer, NULL));
TEST_SIMPLE_WRITE_NOERROR(mpack_write_cstr(&writer, empty_string));

// as should the non-UTF-8 cstr writers
// (the utf8_null test here is writing up to the null-terminator which
// is not what is expected, but there is no way to test for that error.
Expand All @@ -1041,6 +1051,11 @@ static void test_write_utf8(void) {
TEST_SIMPLE_WRITE_NOERROR(mpack_write_cstr(&writer, utf8_cesu8));
TEST_SIMPLE_WRITE_NOERROR(mpack_write_cstr(&writer, utf8_wobbly));

// A NULL string or string with 0 length should be accepted
TEST_SIMPLE_WRITE_NOERROR(mpack_write_utf8(&writer, utf8_null, 0));
TEST_SIMPLE_WRITE_NOERROR(mpack_write_utf8(&writer, NULL, 0));
TEST_SIMPLE_WRITE_NOERROR(mpack_write_utf8(&writer, empty_string, 0));

// test UTF-8 cstr writers
// NUL is valid in UTF-8, so we allow it by the non-cstr API. (If you're
// using it to write, you should also using some non-cstr API to
Expand All @@ -1055,6 +1070,10 @@ static void test_write_utf8(void) {
TEST_SIMPLE_WRITE_ERROR(mpack_write_utf8(&writer, utf8_cesu8, (uint32_t)sizeof(utf8_cesu8)-1), mpack_error_invalid);
TEST_SIMPLE_WRITE_ERROR(mpack_write_utf8(&writer, utf8_wobbly, (uint32_t)sizeof(utf8_wobbly)-1), mpack_error_invalid);

// A NULL string or string with 0 length should be accepted
TEST_SIMPLE_WRITE_NOERROR(mpack_write_utf8_cstr(&writer, NULL));
TEST_SIMPLE_WRITE_NOERROR(mpack_write_utf8_cstr(&writer, empty_string));

// test UTF-8 cstr writers
TEST_SIMPLE_WRITE_NOERROR(mpack_write_utf8_cstr(&writer, utf8_null)); // again, up to null-terminator, which is valid...
TEST_SIMPLE_WRITE_NOERROR(mpack_write_utf8_cstr(&writer, utf8_valid));
Expand All @@ -1069,6 +1088,7 @@ static void test_write_utf8(void) {
// some basic tests for utf8_cstr_or_nil
TEST_SIMPLE_WRITE("\xa5hello", mpack_write_utf8_cstr_or_nil(&writer, "hello"));
TEST_SIMPLE_WRITE("\xc0", mpack_write_utf8_cstr_or_nil(&writer, NULL));
TEST_SIMPLE_WRITE("\xa0", mpack_write_utf8_cstr_or_nil(&writer, empty_string));
TEST_SIMPLE_WRITE_ERROR(mpack_write_utf8_cstr_or_nil(&writer, utf8_invalid), mpack_error_invalid);
}

Expand Down Expand Up @@ -1216,6 +1236,41 @@ static void test_write_compatibility(void) {
}
}

for (i = 0; i < sizeof(versions) / sizeof(versions[0]); ++i) {
mpack_version_t version = versions[i];
mpack_writer_init(&writer, buf, sizeof(buf));
mpack_writer_set_version(&writer, version);

mpack_start_array(&writer, 2);
mpack_write_cstr(&writer, quick_brown_fox);
mpack_write_bin(&writer, NULL, 0);
mpack_finish_array(&writer);

size_t size = mpack_writer_buffer_used(&writer);
TEST_WRITER_DESTROY_NOERROR(&writer);

if (version == mpack_version_v4) {
if (size != 1 + 3 + strlen(quick_brown_fox) + 1 ) {
TEST_TRUE(false, "incorrect length!");
} else {
TEST_TRUE(memcmp("\x92", buf, 1) == 0);
TEST_TRUE(memcmp("\xda\x00\x2a", buf + 1, 3) == 0);
TEST_TRUE(memcmp(quick_brown_fox, buf + 1 + 3, strlen(quick_brown_fox)) == 0);
TEST_TRUE(memcmp("\xa0", buf + 1 + 3 + strlen(quick_brown_fox), 1) == 0);
}
} else {
if (size != 1 + 2 + strlen(quick_brown_fox) + 2) {
TEST_TRUE(false, "incorrect length!");
} else {
TEST_TRUE(memcmp("\x92", buf, 1) == 0);
TEST_TRUE(memcmp("\xd9\x2a", buf + 1, 2) == 0);
TEST_TRUE(memcmp(quick_brown_fox, buf + 1 + 2, strlen(quick_brown_fox)) == 0);
TEST_TRUE(memcmp("\xc4\x00", buf + 1 + 2 + strlen(quick_brown_fox), 2) == 0);
}
}
}


#if MPACK_EXTENSIONS
// test ext break in v4 mode
mpack_writer_init(&writer, buf, sizeof(buf));
Expand Down