if exists and not empty, use its as history file's path.
---
 frontend/readline.c | 19 +++++++++++++++++--
 main.c              |  3 ++-
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/frontend/readline.c b/frontend/readline.c
index 19880fd..6cb53ec 100644
--- a/frontend/readline.c
+++ b/frontend/readline.c
@@ -38,8 +38,23 @@ static void sigint_handler(int n) {
 
 static char *get_history_path(void) {
 	const char *home = getenv("HOME");
-	int len = snprintf(NULL, 0, "%s/.mrsh_history", home);
-	char *path = malloc(len + 1);
+	extern struct mrsh_state *state;
+	const char *histfile = mrsh_env_get(state, "HISTFILE", NULL);
+	int len;
+	char *path;
+
+	if (histfile != NULL && strcmp(histfile, "") != 0) {
+		len = strlen(histfile);
+		path = malloc(len + 1);
+		if (path == NULL) {
+			return NULL;
+		}
+		snprintf(path, len + 1, "%s", histfile);
+		return path;
+	}
+
+	len = snprintf(NULL, 0, "%s/.mrsh_history", home);
+	path = malloc(len + 1);
 	if (path == NULL) {
 		return NULL;
 	}
diff --git a/main.c b/main.c
index 0f433d2..25e278e 100644
--- a/main.c
+++ b/main.c
@@ -15,9 +15,10 @@
 #include "frontend.h"
 
 extern char **environ;
+struct mrsh_state *state;
 
 int main(int argc, char *argv[]) {
-	struct mrsh_state *state = mrsh_state_create();
+	state = mrsh_state_create();
 
 	struct mrsh_init_args init_args = {0};
 	if (mrsh_process_args(state, &init_args, argc, argv) != 0) {
-- 
2.30.0

On Sunday, January 17th, 2021 at 9:25 AM, Merlin <merlin@nixnetmail.com> wrote:

> if exists and not empty, use its as history file's path.

Sorry for the delay.

The idea looks good to me. Here are two comments.

> ---
>  frontend/readline.c | 19 +++++++++++++++++--
>  main.c              |  3 ++-
>  2 files changed, 19 insertions(+), 3 deletions(-)
> 

> diff --git a/frontend/readline.c b/frontend/readline.c
> index 19880fd..6cb53ec 100644
> --- a/frontend/readline.c
> +++ b/frontend/readline.c
> @@ -38,8 +38,23 @@ static void sigint_handler(int n) {
> 

>  static char *get_history_path(void) {
>  	const char *home = getenv("HOME");
> -	int len = snprintf(NULL, 0, "%s/.mrsh_history", home);
> -	char *path = malloc(len + 1);
> +	extern struct mrsh_state *state;
> +	const char *histfile = mrsh_env_get(state, "HISTFILE", NULL);
> +	int len;
> +	char *path;
> +
> +	if (histfile != NULL && strcmp(histfile, "") != 0) {
> +		len = strlen(histfile);
> +		path = malloc(len + 1);
> +		if (path == NULL) {
> +			return NULL;
> +		}
> +		snprintf(path, len + 1, "%s", histfile);
> +		return path;

We can use strdup here.

> +	}
> +
> +	len = snprintf(NULL, 0, "%s/.mrsh_history", home);
> +	path = malloc(len + 1);
>  	if (path == NULL) {
>  		return NULL;
>  	}
> diff --git a/main.c b/main.c
> index 0f433d2..25e278e 100644
> --- a/main.c
> +++ b/main.c
> @@ -15,9 +15,10 @@
>  #include "frontend.h"
> 

>  extern char **environ;
> +struct mrsh_state *state;

Hm, I'm not a fan of having this global variable here. Can't we pass it to
get_history_path without this trick?

- I didn't know about strdup

- I was so blind that I didn't even look for which function calls 
get_history_path, which is defined next to get_history_path and it takes 
state as a parameter