[v2,7/9] gdbstub: Replace alloca() + memset(0) by g_new0()

Commit Message

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

The ALLOCA(3) man-page mentions its "use is discouraged".

Replace the alloca() and memset(0) calls by g_new0().

Signed-off-by: Philippe Mathieu-Daudé <[e-mail]>
---
 gdbstub.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

Comments

Alex Bennée May 6, 2021, 7:22 p.m. UTC | #1

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

> The ALLOCA(3) man-page mentions its "use is discouraged".
>
> Replace the alloca() and memset(0) calls by g_new0().
>
> Signed-off-by: Philippe Mathieu-Daudé <[e-mail]>

Please see:

  Subject: [ALT PATCH] gdbstub: Replace GdbCmdContext with plain g_array()
  Date: Thu,  6 May 2021 17:07:41 +0100
  Message-Id: <[e-mail]>

which also includes elements of 6/9 which can be kept split off.

> ---
>  gdbstub.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/gdbstub.c b/gdbstub.c
> index 7cee2fb0f1f..666053bf590 100644
> --- a/gdbstub.c
> +++ b/gdbstub.c
> @@ -1487,14 +1487,13 @@ static int process_string_cmd(void *user_ctx, const char *data,
>          if (cmd->schema) {
>              int schema_len = strlen(cmd->schema);
>              int max_num_params = schema_len / 2;
> +            g_autofree GdbCmdVariant *params = NULL;
>  
>              if (schema_len % 2) {
>                  return -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 = params = g_new0(GdbCmdVariant, max_num_params);
>  
>              if (cmd_parse_params(&data[strlen(cmd->cmd)], cmd->schema,
>                                   gdb_ctx.params, &gdb_ctx.num_params)) {

Patch

diff --git a/gdbstub.c b/gdbstub.c
index 7cee2fb0f1f..666053bf590 100644
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -1487,14 +1487,13 @@  static int process_string_cmd(void *user_ctx, const char *data,
         if (cmd->schema) {
             int schema_len = strlen(cmd->schema);
             int max_num_params = schema_len / 2;
+            g_autofree GdbCmdVariant *params = NULL;
 
             if (schema_len % 2) {
                 return -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 = params = g_new0(GdbCmdVariant, max_num_params);
 
             if (cmd_parse_params(&data[strlen(cmd->cmd)], cmd->schema,
                                  gdb_ctx.params, &gdb_ctx.num_params)) {