feat(path): add sentry__path_copy for large attachments (#1680)

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: jpnurmi

CMakeLists.txt

@@ -422,6 +422,15 @@ endif()
 include(CheckTypeSize)
 check_type_size("long" CMAKE_SIZEOF_LONG)
 
+if(LINUX)
+	include(CheckSymbolExists)
+	list(APPEND CMAKE_REQUIRED_DEFINITIONS -D_GNU_SOURCE)
+	check_symbol_exists(copy_file_range "unistd.h" HAVE_COPY_FILE_RANGE)
+	if(HAVE_COPY_FILE_RANGE)
+		target_compile_definitions(sentry PRIVATE SENTRY_HAVE_COPY_FILE_RANGE)
+	endif()
+endif()
+
 # https://gitlab.kitware.com/cmake/cmake/issues/18393
 if(SENTRY_BUILD_SHARED_LIBS)
 	if(APPLE)

src/path/sentry_path_unix.c

@@ -21,6 +21,7 @@
 #include <unistd.h>
 
 #ifdef SENTRY_PLATFORM_DARWIN
+#    include <copyfile.h>
 #    include <mach-o/dyld.h>
 #endif
 
@@ -333,6 +334,71 @@ sentry__path_rename(const sentry_path_t *src, const sentry_path_t *dst)
     return status == 0 ? 0 : 1;
 }
 
+int
+sentry__path_copy(const sentry_path_t *src, const sentry_path_t *dst)
+{
+#ifdef SENTRY_PLATFORM_DARWIN
+    return copyfile(src->path, dst->path, NULL, COPYFILE_DATA) == 0 ? 0 : 1;
+#else
+    int src_fd = open(src->path, O_RDONLY);
+    if (src_fd < 0) {
+        return 1;
+    }
+    int dst_fd = open(dst->path, O_WRONLY | O_CREAT | O_TRUNC,
+        S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH);
+    if (dst_fd < 0) {
+        close(src_fd);
+        return 1;
+    }
+
+    int rv = 0;
+
+#    ifdef SENTRY_HAVE_COPY_FILE_RANGE
+    while (true) {
+        ssize_t n
+            = copy_file_range(src_fd, NULL, dst_fd, NULL, SIZE_MAX / 2, 0);
+        if (n > 0) {
+            continue;
+        } else if (n == 0) {
+            goto done;
+        } else if (errno == EAGAIN || errno == EINTR) {
+            continue;
+        } else if (errno == ENOSYS || errno == EXDEV || errno == EOPNOTSUPP
+            || errno == EINVAL) {
+            break;
+        } else {
+            rv = 1;
+            goto done;
+        }
+    }
+#    endif
+
+    {
+        char buf[16384];
+        while (true) {
+            ssize_t n = read(src_fd, buf, sizeof(buf));
+            if (n < 0 && (errno == EAGAIN || errno == EINTR)) {
+                continue;
+            } else if (n <= 0) {
+                rv = n < 0;
+                break;
+            }
+            if (write_loop(dst_fd, buf, (size_t)n) != 0) {
+                rv = 1;
+                break;
+            }
+        }
+    }
+
+#    ifdef SENTRY_HAVE_COPY_FILE_RANGE
+done:
+#    endif
+    close(src_fd);
+    close(dst_fd);
+    return rv;
+#endif
+}
+
 int
 sentry__path_create_dir_all(const sentry_path_t *path)
 {

src/path/sentry_path_windows.c

@@ -524,6 +524,15 @@ sentry__path_rename(const sentry_path_t *src, const sentry_path_t *dst)
     return MoveFileExW(src_w, dst_w, MOVEFILE_REPLACE_EXISTING) ? 0 : 1;
 }
 
+int
+sentry__path_copy(const sentry_path_t *src, const sentry_path_t *dst)
+{
+    if (!src->path_w || !dst->path_w) {
+        return 1;
+    }
+    return CopyFileW(src->path_w, dst->path_w, FALSE) ? 0 : 1;
+}
+
 int
 sentry__path_create_dir_all(const sentry_path_t *path)
 {

src/sentry_path.h

@@ -167,6 +167,12 @@ int sentry__path_remove_all(const sentry_path_t *path);
  */
 int sentry__path_rename(const sentry_path_t *src, const sentry_path_t *dst);
 
+/**
+ * Copy the file from `src` to `dst`.
+ * Returns 0 on success.
+ */
+int sentry__path_copy(const sentry_path_t *src, const sentry_path_t *dst);
+
 /**
  * This will create the directory referred to by `path`, and any non-existing
  * parent directory.

tests/unit/test_path.c

@@ -393,3 +393,52 @@ SENTRY_TEST(path_basename)
     TEST_CHECK(!sentry__path_basename(path, ".tar.gz"));
     sentry__path_free(path);
 }
+
+SENTRY_TEST(path_copy)
+{
+#if defined(SENTRY_PLATFORM_NX)
+    SKIP_TEST();
+#endif
+    sentry_path_t *src
+        = sentry__path_from_str(SENTRY_TEST_PATH_PREFIX ".copy-src");
+    TEST_ASSERT(!!src);
+    sentry_path_t *dst
+        = sentry__path_from_str(SENTRY_TEST_PATH_PREFIX ".copy-dst");
+    TEST_ASSERT(!!dst);
+
+    // cleanup
+    sentry__path_remove_all(src);
+    sentry__path_remove_all(dst);
+
+    // copy file with content preserved
+    sentry__path_write_buffer(src, "hello", 5);
+    TEST_CHECK(sentry__path_copy(src, dst) == 0);
+    TEST_CHECK(sentry__path_is_file(src));
+    TEST_CHECK(sentry__path_is_file(dst));
+    size_t len = 0;
+    char *buf = sentry__path_read_to_buffer(dst, &len);
+    TEST_ASSERT(!!buf);
+    TEST_CHECK(len == 5);
+    TEST_CHECK(memcmp(buf, "hello", 5) == 0);
+    sentry_free(buf);
+    sentry__path_remove(dst);
+
+    // overwrite existing dst
+    sentry__path_write_buffer(dst, "dst-data", 8);
+    TEST_CHECK(sentry__path_copy(src, dst) == 0);
+    TEST_CHECK(sentry__path_is_file(src));
+    buf = sentry__path_read_to_buffer(dst, &len);
+    TEST_ASSERT(!!buf);
+    TEST_CHECK(len == 5);
+    TEST_CHECK(memcmp(buf, "hello", 5) == 0);
+    sentry_free(buf);
+    sentry__path_remove(dst);
+
+    // copy nonexistent src
+    sentry__path_remove(src);
+    TEST_CHECK(sentry__path_copy(src, dst) != 0);
+
+    sentry__path_remove_all(dst);
+    sentry__path_free(dst);
+    sentry__path_free(src);
+}

tests/unit/tests.inc

@@ -189,6 +189,7 @@ XX(overflow_spans)
 XX(page_allocator)
 XX(path_basename)
 XX(path_basics)
+XX(path_copy)
 XX(path_current_exe)
 XX(path_directory)
 XX(path_from_str_n_wo_null_termination)