changes for adding new features --snapshot,

> ---
>   builtin/commit.c |   2 +
>   snapshot.c       | 108 +++++++++++++++++++++++++++++++++++++++++++++++
>   snapshot.h       |  13 ++++++
>   3 files changed, 123 insertions(+)
>   create mode 100644 snapshot.c
>   create mode 100644 snapshot.h
> 
> diff --git a/builtin/commit.c b/builtin/commit.c
> index 0243f17d53..e880409be7 100644
> --- a/builtin/commit.c
> +++ b/builtin/commit.c
> @@ -43,6 +43,7 @@
>   #include "commit-graph.h"
>   #include "pretty.h"
>   #include "trailer.h"
> +#include "snapshot.c"
> 
>   static const char * const builtin_commit_usage[] = {
>    N_("git commit [-a | --interactive | --patch] [-s] [-v] [-u[<mode>]]
> [--amend]\n"
> @@ -1545,6 +1546,7 @@ struct repository *repo UNUSED)
>    int fd;
>    struct object_id oid;
>    static struct option builtin_status_options[] = {
> + OPT_BOOLEAN(0, "snapshot", &opts.snapshot, "Create snapshot of staged files")
>    OPT__VERBOSE(&verbose, N_("be verbose")),
>    OPT_SET_INT('s', "short", &status_format,
>        N_("show status concisely"), STATUS_FORMAT_SHORT),
> diff --git a/snapshot.c b/snapshot.c
> new file mode 100644
> index 0000000000..8c117a7314
> --- /dev/null
> +++ b/snapshot.c
> @@ -0,0 +1,108 @@
> +#include "snapshot.h"
> +#include "run-command.h"
> +#include "strbuf.h"
> +#include "utf8.h"
> +#include <time.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <sys/stat.h>
> +#include <errno.h>
> +
> +#define DEFAULT_SNAPSHOT_DIR ".git/snapshots"
> +/*
> +## Idea
> +The `--snapshot` flag would create a copy of all staged files in a
> timestamped folder before the commit is made. Users could configure
> the snapshot folder, defaulting to `.git/snapshots`.
> +
> +## Example Usage
> +
> +# Enable snapshot feature
> +git config snapshot.enable true
> +
> +# Optional: configure snapshot folder
> +git config snapshot.folder "../snapshots"
> +
> +# Stage files and commit with snapshot
> +git add .
> +git commit -m "Initial commit" --snapshot
> +
> +# Example snapshot folder created:
> +# ../snapshots/2025-12-17_14-30-00_Initial_commit/
> +
> +# Notes:
> +these codes are never tested, I send it just to know if it fits to
> your development
> +*/
> +
> +// Get snapshot folder from config, or fallback to default
> +static char *get_snapshot_dir(void) {
> +    const char *cfg_dir = git_config_get_string("snapshot.folder");
> +    if (cfg_dir && *cfg_dir)
> +        return strdup(cfg_dir);
> +    return strdup(DEFAULT_SNAPSHOT_DIR);
> +}
> +
> +// Check if snapshot is enabled
> +int snapshot_enabled(void) {
> +    const char *val = git_config_get_string("snapshot.enable");
> +    return val && strcmp(val, "true") == 0;
> +}
> +
> +// Get current timestamp for folder name
> +static void get_timestamp(char *buffer, size_t size) {
> +    time_t now = time(NULL);
> +    struct tm *tm_info = localtime(&now);
> +    strftime(buffer, size, "%Y-%m-%d_%H-%M-%S", tm_info);
> +}
> +
> +// Create snapshot of staged files
> +int create_snapshot(const char *message) {
> +    char timestamp[64];
> +    char snapshot_path[1024];
> +
> +    char *snapshot_dir = get_snapshot_dir();
> +    if (!snapshot_dir) {
> +        fprintf(stderr, "Failed to get snapshot directory\n");
> +        return -1;
> +    }
> +
> +    // Ensure base folder exists
> +    if (mkdir(snapshot_dir, 0755) != 0 && errno != EEXIST) {
> +        perror("mkdir snapshot_dir");
> +        free(snapshot_dir);
> +        return -1;
> +    }
> +
> +    get_timestamp(timestamp, sizeof(timestamp));
> +
> +    // Sanitize commit message
> +    char sanitized_msg[512];
> +    snprintf(sanitized_msg, sizeof(sanitized_msg), "%s", message);
> +    for (char *p = sanitized_msg; *p; p++)
> +        if (*p == ' ') *p = '_';
> +
> +    // Create snapshot folder path
> +    snprintf(snapshot_path, sizeof(snapshot_path), "%s/%s_%s",
> snapshot_dir, timestamp, sanitized_msg);
> +
> +    if (mkdir(snapshot_path, 0755) != 0) {
> +        perror("mkdir snapshot_path");
> +        free(snapshot_dir);
> +        return -1;
> +    }
> +
> +    // Copy staged files
> +    char cmd[2048];
> +    snprintf(cmd, sizeof(cmd),
> +             "git diff --name-only --cached | xargs -I{} cp --parents
> {} \"%s\"",
> +             snapshot_path);
> +
> +    int ret = system(cmd);
> +    if (ret != 0) {
> +        fprintf(stderr, "Failed to copy staged files\n");
> +        free(snapshot_dir);
> +        return -1;
> +    }
> +
> +    printf("Snapshot created at %s\n", snapshot_path);
> +    free(snapshot_dir);
> +    return 0;
> +}
> diff --git a/snapshot.h b/snapshot.h
> new file mode 100644
> index 0000000000..7542538f1f
> --- /dev/null
> +++ b/snapshot.h
> @@ -0,0 +1,13 @@
> +#ifndef SNAPSHOT_H
> +#define SNAPSHOT_H
> +
> +#include "cache.h"
> +#include "dir.h"
> +
> +// Check if snapshot feature is enabled
> +int snapshot_enabled(void);
> +
> +// Create snapshot of staged files with commit message
> +int create_snapshot(const char *message);
> +
> +#endif // SNAPSHOT_H

> It would be helpful if there was a commit message explaining what this
> new feature is and why it is needed. There are some comments in the code
> explaining what it does but not why it is useful. Given that a commit is
> a snapshot of the working copy I'm not sure why you'd want to save an
> additional copy.