diff options
Diffstat (limited to 'reftable/refname.c')
| -rw-r--r-- | reftable/refname.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/reftable/refname.c b/reftable/refname.c new file mode 100644 index 0000000..9573496 --- /dev/null +++ b/reftable/refname.c @@ -0,0 +1,209 @@ +/* + Copyright 2020 Google LLC + + Use of this source code is governed by a BSD-style + license that can be found in the LICENSE file or at + https://developers.google.com/open-source/licenses/bsd +*/ + +#include "system.h" +#include "reftable-error.h" +#include "basics.h" +#include "refname.h" +#include "reftable-iterator.h" + +struct find_arg { + char **names; + const char *want; +}; + +static int find_name(size_t k, void *arg) +{ + struct find_arg *f_arg = arg; + return strcmp(f_arg->names[k], f_arg->want) >= 0; +} + +static int modification_has_ref(struct modification *mod, const char *name) +{ + struct reftable_ref_record ref = { NULL }; + int err = 0; + + if (mod->add_len > 0) { + struct find_arg arg = { + .names = mod->add, + .want = name, + }; + int idx = binsearch(mod->add_len, find_name, &arg); + if (idx < mod->add_len && !strcmp(mod->add[idx], name)) { + return 0; + } + } + + if (mod->del_len > 0) { + struct find_arg arg = { + .names = mod->del, + .want = name, + }; + int idx = binsearch(mod->del_len, find_name, &arg); + if (idx < mod->del_len && !strcmp(mod->del[idx], name)) { + return 1; + } + } + + err = reftable_table_read_ref(&mod->tab, name, &ref); + reftable_ref_record_release(&ref); + return err; +} + +static void modification_release(struct modification *mod) +{ + /* don't delete the strings themselves; they're owned by ref records. + */ + FREE_AND_NULL(mod->add); + FREE_AND_NULL(mod->del); + mod->add_len = 0; + mod->del_len = 0; +} + +static int modification_has_ref_with_prefix(struct modification *mod, + const char *prefix) +{ + struct reftable_iterator it = { NULL }; + struct reftable_ref_record ref = { NULL }; + int err = 0; + + if (mod->add_len > 0) { + struct find_arg arg = { + .names = mod->add, + .want = prefix, + }; + int idx = binsearch(mod->add_len, find_name, &arg); + if (idx < mod->add_len && + !strncmp(prefix, mod->add[idx], strlen(prefix))) + goto done; + } + err = reftable_table_seek_ref(&mod->tab, &it, prefix); + if (err) + goto done; + + while (1) { + err = reftable_iterator_next_ref(&it, &ref); + if (err) + goto done; + + if (mod->del_len > 0) { + struct find_arg arg = { + .names = mod->del, + .want = ref.refname, + }; + int idx = binsearch(mod->del_len, find_name, &arg); + if (idx < mod->del_len && + !strcmp(ref.refname, mod->del[idx])) { + continue; + } + } + + if (strncmp(ref.refname, prefix, strlen(prefix))) { + err = 1; + goto done; + } + err = 0; + goto done; + } + +done: + reftable_ref_record_release(&ref); + reftable_iterator_destroy(&it); + return err; +} + +static int validate_refname(const char *name) +{ + while (1) { + char *next = strchr(name, '/'); + if (!*name) { + return REFTABLE_REFNAME_ERROR; + } + if (!next) { + return 0; + } + if (next - name == 0 || (next - name == 1 && *name == '.') || + (next - name == 2 && name[0] == '.' && name[1] == '.')) + return REFTABLE_REFNAME_ERROR; + name = next + 1; + } + return 0; +} + +int validate_ref_record_addition(struct reftable_table tab, + struct reftable_ref_record *recs, size_t sz) +{ + struct modification mod = { + .tab = tab, + .add = reftable_calloc(sizeof(char *) * sz), + .del = reftable_calloc(sizeof(char *) * sz), + }; + int i = 0; + int err = 0; + for (; i < sz; i++) { + if (reftable_ref_record_is_deletion(&recs[i])) { + mod.del[mod.del_len++] = recs[i].refname; + } else { + mod.add[mod.add_len++] = recs[i].refname; + } + } + + err = modification_validate(&mod); + modification_release(&mod); + return err; +} + +static void strbuf_trim_component(struct strbuf *sl) +{ + while (sl->len > 0) { + int is_slash = (sl->buf[sl->len - 1] == '/'); + strbuf_setlen(sl, sl->len - 1); + if (is_slash) + break; + } +} + +int modification_validate(struct modification *mod) +{ + struct strbuf slashed = STRBUF_INIT; + int err = 0; + int i = 0; + for (; i < mod->add_len; i++) { + err = validate_refname(mod->add[i]); + if (err) + goto done; + strbuf_reset(&slashed); + strbuf_addstr(&slashed, mod->add[i]); + strbuf_addstr(&slashed, "/"); + + err = modification_has_ref_with_prefix(mod, slashed.buf); + if (err == 0) { + err = REFTABLE_NAME_CONFLICT; + goto done; + } + if (err < 0) + goto done; + + strbuf_reset(&slashed); + strbuf_addstr(&slashed, mod->add[i]); + while (slashed.len) { + strbuf_trim_component(&slashed); + err = modification_has_ref(mod, slashed.buf); + if (err == 0) { + err = REFTABLE_NAME_CONFLICT; + goto done; + } + if (err < 0) + goto done; + } + } + err = 0; +done: + strbuf_release(&slashed); + return err; +} |