Re: [PATCH 3/9] fsck: factor out msg_id_info[] lazy initialization code

[Eric Sunshine]

On Thu, May 10, 2018 at 10:19 AM Nguyễn Thái Ngọc Duy 
wrote:
> This array will be used by some other function than parse_msg_id() in
> the following commit. Factor out this prep code so it could be called
> from that one.

> Signed-off-by: Nguyễn Thái Ngọc Duy 
> ---
> diff --git a/fsck.c b/fsck.c
> @@ -84,26 +84,32 @@ static struct {
> -static int parse_msg_id(const char *text)
> +static void prepare_msg_ids(void)
>   {
> -   if (!msg_id_info[0].downcased) {
> -   /* convert id_string to lower case, without underscores.
*/
> -   for (i = 0; i < FSCK_MSG_MAX; i++) {
> -   [...]
> -   }
> +   /* convert id_string to lower case, without underscores. */
> +   for (i = 0; i < FSCK_MSG_MAX; i++) {
> +   [...]
>  }
> +}
> +
> +static int parse_msg_id(const char *text)
> +{
> +   if (!msg_id_info[0].downcased)
> +   prepare_msg_ids();

If you move the "if (!msg_id_info...)" conditional into the new
parpare_msg_ids() function, then it becomes self-contained; it takes care
of avoiding double-initialization so callers don't have to worry or know
about it. (Doing so would also make the diff less noisy.)

Not at all worth a re-roll.

[PATCH 3/9] fsck: factor out msg_id_info[] lazy initialization code

[Nguyễn Thái Ngọc Duy]

This array will be used by some other function than parse_msg_id() in
the following commit. Factor out this prep code so it could be called
from that one.

Signed-off-by: Nguyễn Thái Ngọc Duy 
---
 fsck.c | 38 ++
 1 file changed, 22 insertions(+), 16 deletions(-)

diff --git a/fsck.c b/fsck.c
index 9218c2a643..f2534abd44 100644
--- a/fsck.c
+++ b/fsck.c
@@ -84,26 +84,32 @@ static struct {
 };
 #undef MSG_ID
 
-static int parse_msg_id(const char *text)
+static void prepare_msg_ids(void)
 {
int i;
 
-   if (!msg_id_info[0].downcased) {
-   /* convert id_string to lower case, without underscores. */
-   for (i = 0; i < FSCK_MSG_MAX; i++) {
-   const char *p = msg_id_info[i].id_string;
-   int len = strlen(p);
-   char *q = xmalloc(len);
-
-   msg_id_info[i].downcased = q;
-   while (*p)
-   if (*p == '_')
-   p++;
-   else
-   *(q)++ = tolower(*(p)++);
-   *q = '\0';
-   }
+   /* convert id_string to lower case, without underscores. */
+   for (i = 0; i < FSCK_MSG_MAX; i++) {
+   const char *p = msg_id_info[i].id_string;
+   int len = strlen(p);
+   char *q = xmalloc(len);
+
+   msg_id_info[i].downcased = q;
+   while (*p)
+   if (*p == '_')
+   p++;
+   else
+   *(q)++ = tolower(*(p)++);
+   *q = '\0';
}
+}
+
+static int parse_msg_id(const char *text)
+{
+   int i;
+
+   if (!msg_id_info[0].downcased)
+   prepare_msg_ids();
 
for (i = 0; i < FSCK_MSG_MAX; i++)
if (!strcmp(text, msg_id_info[i].downcased))
-- 
2.17.0.705.g3525833791