[v2,6/9] gdbstub: Only call cmd_parse_params() with non-NULL command schema

Commit Message

Philippe Mathieu-Daudé May 6, 2021, 1:37 p.m. UTC

Move the NULL check on command schema buffer from the callee
cmd_parse_params() to the single caller, process_string_cmd().

This simplifies the process_string_cmd() logic.

Signed-off-by: Philippe Mathieu-Daudé <[e-mail]>
---
 gdbstub.c | 27 ++++++++++++---------------
 1 file changed, 12 insertions(+), 15 deletions(-)

Comments

Alex Bennée May 6, 2021, 7:21 p.m. UTC | #1

Philippe Mathieu-Daudé <[e-mail]> writes:

> Move the NULL check on command schema buffer from the callee
> cmd_parse_params() to the single caller, process_string_cmd().
>
> This simplifies the process_string_cmd() logic.
>
> Signed-off-by: Philippe Mathieu-Daudé <[e-mail]>

Reviewed-by: Alex Bennée <[e-mail]>

Patch

diff --git a/gdbstub.c b/gdbstub.c
index 83d47c67325..7cee2fb0f1f 100644
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -1368,12 +1368,9 @@  static int cmd_parse_params(const char *data, const char *schema,
     int curr_param;
     const char *curr_schema, *curr_data;
 
+    assert(schema);
     *num_params = 0;
 
-    if (!schema) {
-        return 0;
-    }
-
     curr_schema = schema;
     curr_param = 0;
     curr_data = data;
@@ -1471,7 +1468,7 @@  static inline int startswith(const char *string, const char *pattern)
 static int process_string_cmd(void *user_ctx, const char *data,
                               const GdbCmdParseEntry *cmds, int num_cmds)
 {
-    int i, schema_len, max_num_params = 0;
+    int i;
     GdbCmdContext gdb_ctx;
 
     if (!cmds) {
@@ -1488,21 +1485,21 @@  static int process_string_cmd(void *user_ctx, const char *data,
         }
 
         if (cmd->schema) {
-            schema_len = strlen(cmd->schema);
+            int schema_len = strlen(cmd->schema);
+            int max_num_params = schema_len / 2;
+
             if (schema_len % 2) {
                 return -2;
             }
 
-            max_num_params = schema_len / 2;
-        }
+            gdb_ctx.params = (GdbCmdVariant *)alloca(sizeof(*gdb_ctx.params)
+                                                     * max_num_params);
+            memset(gdb_ctx.params, 0, sizeof(*gdb_ctx.params) * max_num_params);
 
-        gdb_ctx.params =
-            (GdbCmdVariant *)alloca(sizeof(*gdb_ctx.params) * max_num_params);
-        memset(gdb_ctx.params, 0, sizeof(*gdb_ctx.params) * max_num_params);
-
-        if (cmd_parse_params(&data[strlen(cmd->cmd)], cmd->schema,
-                             gdb_ctx.params, &gdb_ctx.num_params)) {
-            return -1;
+            if (cmd_parse_params(&data[strlen(cmd->cmd)], cmd->schema,
+                                 gdb_ctx.params, &gdb_ctx.num_params)) {
+                return -1;
+            }
         }
 
         cmd->handler(&gdb_ctx, user_ctx);