1 files changed, 123 insertions, 49 deletions

diff --git a/src/blob.c b/src/blob.c
index 4065ffa12..b67f8afa5 100644
--- a/src/blob.c
+++ b/src/blob.c
@@ -11,6 +11,7 @@
 
 #include "common.h"
 #include "blob.h"
+#include "filter.h"
 
 const void *git_blob_rawcontent(git_blob *blob)
 {
@@ -24,6 +25,12 @@ size_t git_blob_rawsize(git_blob *blob)
 	return blob->odb_object->raw.len;
 }
 
+int git_blob__getbuf(git_buf *buffer, git_blob *blob)
+{
+	return git_buf_set(
+		buffer, blob->odb_object->raw.data, blob->odb_object->raw.len);
+}
+
 void git_blob__free(git_blob *blob)
 {
 	git_odb_object_free(blob->odb_object);
@@ -65,15 +72,100 @@ int git_blob_create_frombuffer(git_oid *oid, git_repository *repo, const void *b
 	return GIT_SUCCESS;
 }
 
+static int write_file_stream(git_oid *oid, git_odb *odb, const char *path, git_off_t file_size)
+{
+	int fd, error;
+	char buffer[4096];
+	git_odb_stream *stream = NULL;
+
+	if ((error = git_odb_open_wstream(&stream, odb, file_size, GIT_OBJ_BLOB)) < GIT_SUCCESS)
+		return error;
+
+	if ((fd = p_open(path, O_RDONLY)) < 0) {
+		error = git__throw(GIT_ENOTFOUND, "Failed to create blob. Could not open '%s'", path);
+		goto cleanup;
+	}
+
+	while (file_size > 0) {
+		ssize_t read_len = p_read(fd, buffer, sizeof(buffer));
+
+		if (read_len < 0) {
+			error = git__throw(GIT_EOSERR, "Failed to create blob. Can't read full file");
+			p_close(fd);
+			goto cleanup;
+		}
+
+		stream->write(stream, buffer, read_len);
+		file_size -= read_len;
+	}
+
+	p_close(fd);
+	error = stream->finalize_write(oid, stream);
+
+cleanup:
+	stream->free(stream);
+	return error;
+}
+
+static int write_file_filtered(
+	git_oid *oid,
+	git_odb *odb,
+	const char *full_path,
+	git_vector *filters)
+{
+	int error;
+	git_buf source = GIT_BUF_INIT;
+	git_buf dest = GIT_BUF_INIT;
+
+	error = git_futils_readbuffer(&source, full_path);
+	if (error < GIT_SUCCESS)
+		return error;
+
+	error = git_filters_apply(&dest, &source, filters);
+
+	/* Free the source as soon as possible. This can be big in memory,
+	 * and we don't want to ODB write to choke */
+	git_buf_free(&source);
+
+	if (error == GIT_SUCCESS) {
+		/* Write the file to disk if it was properly filtered */
+		error = git_odb_write(oid, odb, dest.ptr, dest.size, GIT_OBJ_BLOB);
+	}
+
+	git_buf_free(&dest);
+	return GIT_SUCCESS;
+}
+
+static int write_symlink(git_oid *oid, git_odb *odb, const char *path, size_t link_size)
+{
+	char *link_data;
+	ssize_t read_len;
+	int error;
+
+	link_data = git__malloc(link_size);
+	if (!link_data)
+		return GIT_ENOMEM;
+
+	read_len = p_readlink(path, link_data, link_size);
+
+	if (read_len != (ssize_t)link_size) {
+		free(link_data);
+		return git__throw(GIT_EOSERR, "Failed to create blob. Can't read symlink");
+	}
+
+	error = git_odb_write(oid, odb, (void *)link_data, link_size, GIT_OBJ_BLOB);
+	free(link_data);
+	return error;
+}
+
 int git_blob_create_fromfile(git_oid *oid, git_repository *repo, const char *path)
 {
 	int error = GIT_SUCCESS;
 	git_buf full_path = GIT_BUF_INIT;
 	git_off_t size;
-	git_odb_stream *stream = NULL;
 	struct stat st;
 	const char *workdir;
-	git_odb *odb;
+	git_odb *odb = NULL;
 
 	workdir = git_repository_workdir(repo);
 	if (workdir == NULL)
@@ -95,63 +187,45 @@ int git_blob_create_fromfile(git_oid *oid, git_repository *repo, const char *pat
 	if (error < GIT_SUCCESS)
 		goto cleanup;
 
-	if ((error = git_odb_open_wstream(&stream, odb, (size_t)size, GIT_OBJ_BLOB)) < GIT_SUCCESS)
-		goto cleanup;
-
 	if (S_ISLNK(st.st_mode)) {
-		char *link_data;
-		ssize_t read_len;
-
-		link_data = git__malloc((size_t)size);
-		if (!link_data) {
-			error = GIT_ENOMEM;
-			goto cleanup;
-		}
-
-		read_len = p_readlink(full_path.ptr, link_data, (size_t)size);
-
-		if (read_len != (ssize_t)size) {
-			error = git__throw(GIT_EOSERR, "Failed to create blob. Can't read symlink");
-			free(link_data);
-			goto cleanup;
-		}
-
-		stream->write(stream, link_data, (size_t)size);
-		free(link_data);
-
+		error = write_symlink(oid, odb, full_path.ptr, (size_t)size);
 	} else {
-		int fd;
-		char buffer[2048];
-
-		if ((fd = p_open(full_path.ptr, O_RDONLY)) < 0) {
-			error = git__throw(GIT_ENOTFOUND, "Failed to create blob. Could not open '%s'", full_path.ptr);
-			goto cleanup;
-		}
-
-		while (size > 0) {
-			ssize_t read_len = p_read(fd, buffer, sizeof(buffer));
+		git_vector write_filters = GIT_VECTOR_INIT;
+		int filter_count;
 
-			if (read_len < 0) {
-				error = git__throw(GIT_EOSERR, "Failed to create blob. Can't read full file");
-				p_close(fd);
-				goto cleanup;
-			}
+		/* Load the filters for writing this file to the ODB */
+		filter_count = git_filters_load(&write_filters, repo, path, GIT_FILTER_TO_ODB);
 
-			stream->write(stream, buffer, read_len);
-			size -= read_len;
+		if (filter_count < 0) {
+			/* Negative value means there was a critical error */
+			error = filter_count;
+			goto cleanup;
+		} else if (filter_count == 0) {
+			/* No filters need to be applied to the document: we can stream
+			 * directly from disk */
+			error = write_file_stream(oid, odb, full_path.ptr, size);
+		} else {
+			/* We need to apply one or more filters */
+			error = write_file_filtered(oid, odb, full_path.ptr, &write_filters);
 		}
 
-		p_close(fd);
+		git_filters_free(&write_filters);
+
+		/*
+		 * TODO: eventually support streaming filtered files, for files which are bigger
+		 * than a given threshold. This is not a priority because applying a filter in
+		 * streaming mode changes the final size of the blob, and without knowing its
+		 * final size, the blob cannot be written in stream mode to the ODB.
+		 *
+		 * The plan is to do streaming writes to a tempfile on disk and then opening
+		 * streaming that file to the ODB, using `write_file_stream`.
+		 *
+		 * CAREFULLY DESIGNED APIS YO
+		 */
 	}
 
-	error = stream->finalize_write(oid, stream);
-
 cleanup:
-	if (stream)
-		stream->free(stream);
-
 	git_buf_free(&full_path);
-
 	return error;
 }