Git 2.32

[git] / ls-refs.c

#include "cache.h"
#include "repository.h"
#include "refs.h"
#include "remote.h"
#include "strvec.h"
#include "ls-refs.h"
#include "pkt-line.h"
#include "config.h"

static int config_read;
static int advertise_unborn;
static int allow_unborn;

static void ensure_config_read(void)
{
        const char *str = NULL;

        if (config_read)
                return;

        if (repo_config_get_string_tmp(the_repository, "lsrefs.unborn", &str)) {
                /*
                 * If there is no such config, advertise and allow it by
                 * default.
                 */
                advertise_unborn = 1;
                allow_unborn = 1;
        } else {
                if (!strcmp(str, "advertise")) {
                        advertise_unborn = 1;
                        allow_unborn = 1;
                } else if (!strcmp(str, "allow")) {
                        allow_unborn = 1;
                } else if (!strcmp(str, "ignore")) {
                        /* do nothing */
                } else {
                        die(_("invalid value '%s' for lsrefs.unborn"), str);
                }
        }
        config_read = 1;
}

/*
 * Check if one of the prefixes is a prefix of the ref.
 * If no prefixes were provided, all refs match.
 */
static int ref_match(const struct strvec *prefixes, const char *refname)
{
        int i;

        if (!prefixes->nr)
                return 1; /* no restriction */

        for (i = 0; i < prefixes->nr; i++) {
                const char *prefix = prefixes->v[i];

                if (starts_with(refname, prefix))
                        return 1;
        }

        return 0;
}

struct ls_refs_data {
        unsigned peel;
        unsigned symrefs;
        struct strvec prefixes;
        unsigned unborn : 1;
};

static int send_ref(const char *refname, const struct object_id *oid,
                    int flag, void *cb_data)
{
        struct ls_refs_data *data = cb_data;
        const char *refname_nons = strip_namespace(refname);
        struct strbuf refline = STRBUF_INIT;

        if (ref_is_hidden(refname_nons, refname))
                return 0;

        if (!ref_match(&data->prefixes, refname_nons))
                return 0;

        if (oid)
                strbuf_addf(&refline, "%s %s", oid_to_hex(oid), refname_nons);
        else
                strbuf_addf(&refline, "unborn %s", refname_nons);
        if (data->symrefs && flag & REF_ISSYMREF) {
                struct object_id unused;
                const char *symref_target = resolve_ref_unsafe(refname, 0,
                                                               &unused,
                                                               &flag);

                if (!symref_target)
                        die("'%s' is a symref but it is not?", refname);

                strbuf_addf(&refline, " symref-target:%s",
                            strip_namespace(symref_target));
        }

        if (data->peel && oid) {
                struct object_id peeled;
                if (!peel_iterated_oid(oid, &peeled))
                        strbuf_addf(&refline, " peeled:%s", oid_to_hex(&peeled));
        }

        strbuf_addch(&refline, '\n');
        packet_write(1, refline.buf, refline.len);

        strbuf_release(&refline);
        return 0;
}

static void send_possibly_unborn_head(struct ls_refs_data *data)
{
        struct strbuf namespaced = STRBUF_INIT;
        struct object_id oid;
        int flag;
        int oid_is_null;

        strbuf_addf(&namespaced, "%sHEAD", get_git_namespace());
        if (!resolve_ref_unsafe(namespaced.buf, 0, &oid, &flag))
                return; /* bad ref */
        oid_is_null = is_null_oid(&oid);
        if (!oid_is_null ||
            (data->unborn && data->symrefs && (flag & REF_ISSYMREF)))
                send_ref(namespaced.buf, oid_is_null ? NULL : &oid, flag, data);
        strbuf_release(&namespaced);
}

static int ls_refs_config(const char *var, const char *value, void *data)
{
        /*
         * We only serve fetches over v2 for now, so respect only "uploadpack"
         * config. This may need to eventually be expanded to "receive", but we
         * don't yet know how that information will be passed to ls-refs.
         */
        return parse_hide_refs_config(var, value, "uploadpack");
}

int ls_refs(struct repository *r, struct strvec *keys,
            struct packet_reader *request)
{
        struct ls_refs_data data;

        memset(&data, 0, sizeof(data));
        strvec_init(&data.prefixes);

        ensure_config_read();
        git_config(ls_refs_config, NULL);

        while (packet_reader_read(request) == PACKET_READ_NORMAL) {
                const char *arg = request->line;
                const char *out;

                if (!strcmp("peel", arg))
                        data.peel = 1;
                else if (!strcmp("symrefs", arg))
                        data.symrefs = 1;
                else if (skip_prefix(arg, "ref-prefix ", &out))
                        strvec_push(&data.prefixes, out);
                else if (!strcmp("unborn", arg))
                        data.unborn = allow_unborn;
        }

        if (request->status != PACKET_READ_FLUSH)
                die(_("expected flush after ls-refs arguments"));

        send_possibly_unborn_head(&data);
        if (!data.prefixes.nr)
                strvec_push(&data.prefixes, "");
        for_each_fullref_in_prefixes(get_git_namespace(), data.prefixes.v,
                                     send_ref, &data, 0);
        packet_flush(1);
        strvec_clear(&data.prefixes);
        return 0;
}

int ls_refs_advertise(struct repository *r, struct strbuf *value)
{
        if (value) {
                ensure_config_read();
                if (advertise_unborn)
                        strbuf_addstr(value, "unborn");
        }

        return 1;
}