From: Michael Tremer <michael.tremer@ipfire.org>
Date: Sat, 21 Jun 2025 16:16:55 +0000 (+0000)
Subject: json: Cleanup the JSON parsing interfaces
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d1d1c3482e45cc9acdd9fc47c87fe9ed4ef872d7;p=pakfire.git

json: Cleanup the JSON parsing interfaces

We should not always require the context to have some basic logging.
Instead we can return the error as a string.

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/pakfire/daemon.c b/src/pakfire/daemon.c
index 2b562d5a..567ab3ab 100644
--- a/src/pakfire/daemon.c
+++ b/src/pakfire/daemon.c
@@ -533,14 +533,15 @@ static int pakfire_daemon_recv(struct pakfire_xfer* xfer,
 	struct pakfire_daemon* daemon = data;
 	struct json_object* type = NULL;
 	struct json_object* m = NULL;
+	char* error = NULL;
 	int r;
 
 	const char* job_id = NULL;
 
 	// Parse the JSON message
-	m = pakfire_json_parse(daemon->ctx, message, size);
-	if (!m) {
-		r = -errno;
+	r = pakfire_json_parse(&m, &error, message, size);
+	if (r < 0) {
+		ERROR(daemon->ctx, "Failed to parse JSON message: %s\n", error);
 		goto ERROR;
 	}
 
@@ -592,6 +593,8 @@ static int pakfire_daemon_recv(struct pakfire_xfer* xfer,
 ERROR:
 	if (m)
 		json_object_put(m);
+	if (error)
+		free(error);
 
 	return r;
 }
diff --git a/src/pakfire/json.c b/src/pakfire/json.c
index 0eee8228..116e7910 100644
--- a/src/pakfire/json.c
+++ b/src/pakfire/json.c
@@ -32,67 +32,87 @@ const char* pakfire_json_to_string(struct json_object* json) {
 	return json_object_to_json_string_ext(json, flags);
 }
 
-struct json_object* pakfire_json_parse(
-		struct pakfire_ctx* ctx, const char* buffer, const size_t length) {
+int pakfire_json_parse(struct json_object** json, char** error,
+		const char* buffer, const size_t length) {
 	struct json_tokener* tokener = NULL;
-	struct json_object* json = NULL;
+	struct json_object* object = NULL;
+	enum json_tokener_error e;
+	int r;
 
 	// Create tokener
 	tokener = json_tokener_new();
-	if (!tokener) {
-		ERROR(ctx, "Could not allocate JSON tokener: %m\n");
-		goto ERROR;
-	}
+	if (!tokener)
+		return -ENOMEM;
 
 	// Parse JSON from buffer
-	json = json_tokener_parse_ex(tokener, buffer, length);
-	if (!json) {
-		enum json_tokener_error error = json_tokener_get_error(tokener);
-
-		ERROR(ctx, "JSON parsing error: %s\n", json_tokener_error_desc(error));
-		goto ERROR;
+	object = json_tokener_parse_ex(tokener, buffer, length);
+	if (!object) {
+		// Fetch the error code
+		e = json_tokener_get_error(tokener);
+
+		// Format the error string
+		if (error) {
+			r = asprintf(error, "JSON parsing error: %s\n", json_tokener_error_desc(e));
+			if (r < 0)
+				goto ERROR;
+		}
+
+		// Assume that the input was invalid
+		r = -EBADMSG;
 	}
 
-	// Log what we have parsed
-	DEBUG(ctx, "Parsed JSON:\n%s\n", pakfire_json_to_string(json));
+	// Return the object
+	*json = object;
+	r = 0;
 
 ERROR:
 	if (tokener)
 		json_tokener_free(tokener);
 
-	return json;
+	return r;
 }
 
-static struct json_object* pakfire_json_parse_file(struct pakfire_ctx* ctx, FILE* f) {
-	struct json_object* json = NULL;
+static int pakfire_json_parse_file(struct json_object** json, char** error, FILE* f) {
 	char* buffer = NULL;
 	size_t length = 0;
 	int r;
 
 	// Map everything into memory
 	r = pakfire_mmap(fileno(f), &buffer, &length);
-	if (r)
+	if (r < 0)
 		goto ERROR;
 
 	// Parse
-	json = pakfire_json_parse(ctx, buffer, length);
+	r = pakfire_json_parse(json, error, buffer, length);
 
 ERROR:
 	if (buffer)
 		munmap(buffer, length);
 
-	return json;
+	return r;
 }
 
-struct json_object* pakfire_json_parse_from_file(struct pakfire_ctx* ctx, const char* path) {
-	FILE* f = fopen(path, "r");
-	if (!f)
-		return NULL;
+int pakfire_json_parse_from_file(struct json_object** json, char** error, const char* path) {
+	FILE* f = NULL;
+	int r;
+
+	// Open the file
+	f = fopen(path, "r");
+	if (!f) {
+		r = -errno;
+		goto ERROR;
+	}
+
+	// Parse the payload
+	r = pakfire_json_parse_file(json, error, f);
+	if (r < 0)
+		goto ERROR;
 
-	struct json_object* json = pakfire_json_parse_file(ctx, f);
-	fclose(f);
+ERROR:
+	if (f)
+		fclose(f);
 
-	return json;
+	return r;
 }
 
 struct json_object* pakfire_json_new_object(void) {
diff --git a/src/pakfire/json.h b/src/pakfire/json.h
index 2023ccd1..b6a2d3ef 100644
--- a/src/pakfire/json.h
+++ b/src/pakfire/json.h
@@ -31,11 +31,11 @@
 const char* pakfire_json_to_string(struct json_object* json);
 
 // Parse
-struct json_object* pakfire_json_parse(struct pakfire_ctx* ctx,
+int pakfire_json_parse(struct json_object** json, char** error,
 	const char* buffer, const size_t length);
 
 // Parse from file
-struct json_object* pakfire_json_parse_from_file(struct pakfire_ctx* ctx, const char* path);
+int pakfire_json_parse_from_file(struct json_object** json, char** error, const char* path);
 
 struct json_object* pakfire_json_new_object(void);
 
diff --git a/src/pakfire/jwt.c b/src/pakfire/jwt.c
index 4474104e..0682650d 100644
--- a/src/pakfire/jwt.c
+++ b/src/pakfire/jwt.c
@@ -89,6 +89,7 @@ ERROR:
 }
 
 int pakfire_jwt_payload(struct pakfire_ctx* ctx, const char* token, struct json_object** payload) {
+	char* error = NULL;
 	char* p = NULL;
 	size_t l = 0;
 	int r;
@@ -97,13 +98,19 @@ int pakfire_jwt_payload(struct pakfire_ctx* ctx, const char* token, struct json_
 	r = pakfire_jwt_decode_payload(&p, &l, token);
 	if (r < 0) {
 		ERROR(ctx, "Failed to decode the JWT payload: %s\n", strerror(-r));
-		return r;
+		goto ERROR;
 	}
 
 	// Parse the JSON
-	*payload = pakfire_json_parse(ctx, p, l);
-	if (!*payload)
-		return -EINVAL;
+	r = pakfire_json_parse(payload, &error, p, l);
+	if (r < 0) {
+		ERROR(ctx, "Failed to parse JSON payload: %s\n", error);
+		goto ERROR;
+	}
+
+ERROR:
+	if (error)
+		free(error);
 
 	return 0;
 }
diff --git a/src/pakfire/mirrorlist.c b/src/pakfire/mirrorlist.c
index 801061c5..10016b39 100644
--- a/src/pakfire/mirrorlist.c
+++ b/src/pakfire/mirrorlist.c
@@ -140,6 +140,8 @@ ERROR:
 }
 
 int pakfire_mirrorlist_read(struct pakfire_mirrorlist* list, const char* path) {
+	struct json_object* json = NULL;
+	char* error = NULL;
 	int r;
 
 	if (!path || !*path) {
@@ -149,13 +151,14 @@ int pakfire_mirrorlist_read(struct pakfire_mirrorlist* list, const char* path) {
 
 	DEBUG(list->ctx, "Reading mirrorlist from %s\n", path);
 
-	struct json_object* json = pakfire_json_parse_from_file(list->ctx, path);
-	if (!json) {
+	// Parse the file
+	r = pakfire_json_parse_from_file(&json, &error, path);
+	if (r < 0) {
 		// Ignore if path does not exist
 		if (errno == ENOENT)
 			return 0;
 
-		ERROR(list->ctx, "Could not parse mirrorlist from %s: %m\n", path);
+		ERROR(list->ctx, "Could not parse mirrorlist from %s: %s\n", path, error);
 		return 1;
 	}
 
@@ -206,6 +209,8 @@ int pakfire_mirrorlist_read(struct pakfire_mirrorlist* list, const char* path) {
 ERROR:
 	if (json)
 		json_object_put(json);
+	if (error)
+		free(error);
 
 	return r;
 }
diff --git a/src/pakfire/repo.c b/src/pakfire/repo.c
index c0b18fb2..ac627e06 100644
--- a/src/pakfire/repo.c
+++ b/src/pakfire/repo.c
@@ -1055,14 +1055,15 @@ ERROR:
 
 static int pakfire_repo_read_metadata(struct pakfire_repo* repo, const char* path) {
 	struct json_object* json = NULL;
+	char* error = NULL;
 	int r;
 
 	DEBUG(repo->ctx, "Reading repository metadata from %s...\n", path);
 
 	// Parse the existing metadata
-	json = pakfire_json_parse_from_file(repo->ctx, path);
-	if (!json) {
-		switch (errno) {
+	r = pakfire_json_parse_from_file(&json, &error, path);
+	if (r < 0) {
+		switch (-r) {
 			case ENOENT:
 				// Log some message
 				DEBUG(repo->ctx, "Repository metadata is not available\n");
@@ -1071,8 +1072,7 @@ static int pakfire_repo_read_metadata(struct pakfire_repo* repo, const char* pat
 				return 0;
 
 			default:
-				ERROR(repo->ctx, "Could not parse metadata from %s: %m\n", path);
-				r = -errno;
+				ERROR(repo->ctx, "Could not parse metadata from %s: %s\n", path, error);
 				goto ERROR;
 		}
 	}
@@ -1098,6 +1098,8 @@ ERROR:
 	// Free the parsed JSON object
 	if (json)
 		json_object_put(json);
+	if (error)
+		free(error);
 
 	return r;
 }
@@ -1262,6 +1264,7 @@ static int pakfire_repo_download_metadata(struct pakfire_repo* repo, const char*
 	struct pakfire_buffer buffer = {};
 	struct pakfire_xfer* xfer = NULL;
 	struct json_object* json = NULL;
+	char* error = NULL;
 	int r;
 
 	// Local repositories don't need to download metadata
@@ -1320,9 +1323,9 @@ static int pakfire_repo_download_metadata(struct pakfire_repo* repo, const char*
 	}
 
 	// Parse JSON from buffer
-	json = pakfire_json_parse(repo->ctx, buffer.data, buffer.length);
-	if (!json) {
-		r = -EBADMSG;
+	r = pakfire_json_parse(&json, &error, buffer.data, buffer.length);
+	if (r < 0) {
+		ERROR(repo->ctx, "Failed to parse JSON data: %s\n", error);
 		goto ERROR;
 	}
 
@@ -1361,6 +1364,8 @@ ERROR:
 		json_object_put(json);
 	if (buffer.data)
 		free(buffer.data);
+	if (error)
+		free(error);
 
 	return r;
 }
diff --git a/src/pakfire/xfer.c b/src/pakfire/xfer.c
index 583cab29..21d9c10c 100644
--- a/src/pakfire/xfer.c
+++ b/src/pakfire/xfer.c
@@ -1875,6 +1875,7 @@ static int pakfire_xfer_parse_api_response(struct pakfire_xfer* xfer,
 		const char* buffer, const size_t length, struct json_object** object) {
 	struct json_object* error = NULL;
 	struct json_object* o = NULL;
+	char* e = NULL;
 	int r;
 
 	// Check if we received any data
@@ -1891,10 +1892,9 @@ static int pakfire_xfer_parse_api_response(struct pakfire_xfer* xfer,
 	// XXX Maybe fetch the parser's error message here?!
 
 	// Parse the buffer
-	o = pakfire_json_parse(xfer->ctx, buffer, length);
-	if (!o) {
-		ERROR(xfer->ctx, "Could not parse the response\n");
-		r = -EBADMSG;
+	r = pakfire_json_parse(&o, &e, buffer, length);
+	if (r < 0) {
+		ERROR(xfer->ctx, "Could not parse the response: %s\n", e);
 		goto ERROR;
 	}
 
@@ -1919,6 +1919,8 @@ static int pakfire_xfer_parse_api_response(struct pakfire_xfer* xfer,
 ERROR:
 	if (o)
 		json_object_put(o);
+	if (e)
+		free(e);
 
 	return r;
 }