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Instead, inspect each object that collides with the estimated abbreviation to find the longest common prefix. The focus of this change is to refactor the existing method in a way that clearly does not change the current behavior. In some cases, the new method is slower than the previous method. Later changes will correct all performance loss. Signed-off-by: Derrick Stolee --- sha1_name.c | 57 ++++++++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 42 insertions(+), 15 deletions(-) diff --git a/sha1_name.c b/sha1_name.c index 134ac9742..f2a1ebe49 100644 --- a/sha1_name.c +++ b/sha1_name.c @@ -474,10 +474,32 @@ static unsigned msb(unsigned long val) return r; } -int find_unique_abbrev_r(char *hex, const unsigned char *sha1, int len) +struct min_abbrev_data { + unsigned int init_len; + unsigned int cur_len; + char *hex; +}; + +static int extend_abbrev_len(const struct object_id *oid, void *cb_data) { - int status, exists; + struct min_abbrev_data *mad = cb_data; + + char *hex = oid_to_hex(oid); + unsigned int i = mad->init_len; + while (mad->hex[i] && mad->hex[i] == hex[i]) + i++; + + if (i < GIT_MAX_RAWSZ && i >= mad->cur_len) + mad->cur_len = i + 1; + + return 0; +} +int find_unique_abbrev_r(char *hex, const unsigned char *sha1, int len) +{ + struct disambiguate_state ds; + struct min_abbrev_data mad; + struct object_id oid_ret; if (len < 0) { unsigned long count = approximate_object_count(); /* @@ -503,19 +525,24 @@ int find_unique_abbrev_r(char *hex, const unsigned char *sha1, int len) sha1_to_hex_r(hex, sha1); if (len == GIT_SHA1_HEXSZ || !len) return GIT_SHA1_HEXSZ; - exists = has_sha1_file(sha1); - while (len < GIT_SHA1_HEXSZ) { - struct object_id oid_ret; - status = get_short_oid(hex, len, &oid_ret, GET_OID_QUIETLY); - if (exists - ? !status - : status == SHORT_NAME_NOT_FOUND) { - hex[len] = 0; - return len; - } - len++; - } - return len; + + if (init_object_disambiguation(hex, len, &ds) < 0) + return -1; + + mad.init_len = len; + mad.cur_len = len; + mad.hex = hex; + + ds.fn = extend_abbrev_len; + ds.always_call_fn = 1; + ds.cb_data = (void*)&mad; + + find_short_object_filename(&ds); + find_short_packed_object(&ds); + (void)finish_object_disambiguation(&ds, &oid_ret); + + hex[mad.cur_len] = 0; + return mad.cur_len; } const char *find_unique_abbrev(const unsigned char *sha1, int len) -- 2.14.1.538.g56ec8fc98.dirty