From b3661567cfa604abfa6a67d8e7bbd6db018c3fe6 Mon Sep 17 00:00:00 2001 From: Daniel Barkalow Date: Wed, 14 Sep 2005 23:26:08 -0400 Subject: [PATCH] [PATCH] Add support for alternates in HTTP This tries .../objects/info/http-alternates and then .../objects/info/alternates, looking for a file which specifies where else to download objects and packs from. It currently only supports absolute paths, and doesn't support full URLs. Signed-off-by: Daniel Barkalow Signed-off-by: Junio C Hamano --- http-fetch.c | 169 ++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 134 insertions(+), 35 deletions(-) diff --git a/http-fetch.c b/http-fetch.c index 1a433a984..17051fe43 100644 --- a/http-fetch.c +++ b/http-fetch.c @@ -16,7 +16,17 @@ static CURL *curl; static struct curl_slist *no_pragma_header; -static char *base; +static char *initial_base; + +struct alt_base +{ + char *base; + int got_indices; + struct packed_git *packs; + struct alt_base *next; +}; + +struct alt_base *alt = NULL; static SHA_CTX c; static z_stream stream; @@ -72,11 +82,9 @@ void prefetch(unsigned char *sha1) { } -static int got_indices = 0; - -static struct packed_git *packs = NULL; +static int got_alternates = 0; -static int fetch_index(unsigned char *sha1) +static int fetch_index(struct alt_base *repo, unsigned char *sha1) { char *filename; char *url; @@ -90,9 +98,9 @@ static int fetch_index(unsigned char *sha1) fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1)); - url = xmalloc(strlen(base) + 64); + url = xmalloc(strlen(repo->base) + 64); sprintf(url, "%s/objects/pack/pack-%s.idx", - base, sha1_to_hex(sha1)); + repo->base, sha1_to_hex(sha1)); filename = sha1_pack_index_name(sha1); indexfile = fopen(filename, "w"); @@ -114,22 +122,92 @@ static int fetch_index(unsigned char *sha1) return 0; } -static int setup_index(unsigned char *sha1) +static int setup_index(struct alt_base *repo, unsigned char *sha1) { struct packed_git *new_pack; if (has_pack_file(sha1)) return 0; // don't list this as something we can get - if (fetch_index(sha1)) + if (fetch_index(repo, sha1)) return -1; new_pack = parse_pack_index(sha1); - new_pack->next = packs; - packs = new_pack; + new_pack->next = repo->packs; + repo->packs = new_pack; return 0; } -static int fetch_indices(void) +static int fetch_alternates(char *base) +{ + int ret = 0; + struct buffer buffer; + char *url; + char *data; + int i = 0; + if (got_alternates) + return 0; + data = xmalloc(4096); + buffer.size = 4096; + buffer.posn = 0; + buffer.buffer = data; + + if (get_verbosely) + fprintf(stderr, "Getting alternates list\n"); + + url = xmalloc(strlen(base) + 31); + sprintf(url, "%s/objects/info/http-alternates", base); + + curl_easy_setopt(curl, CURLOPT_FILE, &buffer); + curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, fwrite_buffer); + curl_easy_setopt(curl, CURLOPT_URL, url); + + if (curl_easy_perform(curl) || !buffer.posn) { + sprintf(url, "%s/objects/info/alternates", base); + + curl_easy_setopt(curl, CURLOPT_FILE, &buffer); + curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, fwrite_buffer); + curl_easy_setopt(curl, CURLOPT_URL, url); + + if (curl_easy_perform(curl)) { + return 0; + } + } + + while (i < buffer.posn) { + int posn = i; + while (posn < buffer.posn && data[posn] != '\n') + posn++; + if (data[posn] == '\n') { + if (data[i] == '/') { + int serverlen = strchr(base + 8, '/') - base; + // skip 'objects' at end + char *target = + xmalloc(serverlen + posn - i - 6); + struct alt_base *newalt; + strncpy(target, base, serverlen); + strncpy(target + serverlen, data + i, + posn - i - 7); + target[serverlen + posn - i - 7] = '\0'; + if (get_verbosely) + fprintf(stderr, + "Also look at %s\n", target); + newalt = xmalloc(sizeof(*newalt)); + newalt->next = alt; + newalt->base = target; + newalt->got_indices = 0; + newalt->packs = NULL; + alt = newalt; + ret++; + } + } + i = posn + 1; + } + got_alternates = 1; + + return ret; +} + +static int fetch_indices(struct alt_base *repo) { unsigned char sha1[20]; char *url; @@ -137,7 +215,7 @@ static int fetch_indices(void) char *data; int i = 0; - if (got_indices) + if (repo->got_indices) return 0; data = xmalloc(4096); @@ -148,8 +226,8 @@ static int fetch_indices(void) if (get_verbosely) fprintf(stderr, "Getting pack list\n"); - url = xmalloc(strlen(base) + 21); - sprintf(url, "%s/objects/info/packs", base); + url = xmalloc(strlen(repo->base) + 21); + sprintf(url, "%s/objects/info/packs", repo->base); curl_easy_setopt(curl, CURLOPT_FILE, &buffer); curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, fwrite_buffer); @@ -160,7 +238,7 @@ static int fetch_indices(void) return error("Unable to get pack index %s", url); } - do { + while (i < buffer.posn) { switch (data[i]) { case 'P': i++; @@ -168,7 +246,7 @@ static int fetch_indices(void) !strncmp(data + i, " pack-", 6) && !strncmp(data + i + 46, ".pack\n", 6)) { get_sha1_hex(data + i + 6, sha1); - setup_index(sha1); + setup_index(repo, sha1); i += 51; break; } @@ -177,13 +255,13 @@ static int fetch_indices(void) i++; } i++; - } while (i < buffer.posn); + } - got_indices = 1; + repo->got_indices = 1; return 0; } -static int fetch_pack(unsigned char *sha1) +static int fetch_pack(struct alt_base *repo, unsigned char *sha1) { char *url; struct packed_git *target; @@ -191,12 +269,11 @@ static int fetch_pack(unsigned char *sha1) FILE *packfile; char *filename; - if (fetch_indices()) + if (fetch_indices(repo)) return -1; - target = find_sha1_pack(sha1, packs); + target = find_sha1_pack(sha1, repo->packs); if (!target) - return error("Couldn't get %s: not separate or in any pack", - sha1_to_hex(sha1)); + return -1; if (get_verbosely) { fprintf(stderr, "Getting pack %s\n", @@ -205,9 +282,9 @@ static int fetch_pack(unsigned char *sha1) sha1_to_hex(sha1)); } - url = xmalloc(strlen(base) + 65); + url = xmalloc(strlen(repo->base) + 65); sprintf(url, "%s/objects/pack/pack-%s.pack", - base, sha1_to_hex(target->sha1)); + repo->base, sha1_to_hex(target->sha1)); filename = sha1_pack_name(target->sha1); packfile = fopen(filename, "w"); @@ -227,7 +304,7 @@ static int fetch_pack(unsigned char *sha1) fclose(packfile); - lst = &packs; + lst = &repo->packs; while (*lst != target) lst = &((*lst)->next); *lst = (*lst)->next; @@ -237,7 +314,7 @@ static int fetch_pack(unsigned char *sha1) return 0; } -int fetch(unsigned char *sha1) +int fetch_object(struct alt_base *repo, unsigned char *sha1) { char *hex = sha1_to_hex(sha1); char *filename = sha1_file_name(sha1); @@ -261,9 +338,9 @@ int fetch(unsigned char *sha1) curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file); curl_easy_setopt(curl, CURLOPT_HTTPHEADER, no_pragma_header); - url = xmalloc(strlen(base) + 50); - strcpy(url, base); - posn = url + strlen(base); + url = xmalloc(strlen(repo->base) + 50); + strcpy(url, repo->base); + posn = url + strlen(repo->base); strcpy(posn, "objects/"); posn += 8; memcpy(posn, hex, 2); @@ -275,9 +352,7 @@ int fetch(unsigned char *sha1) if (curl_easy_perform(curl)) { unlink(filename); - if (fetch_pack(sha1)) - return error("Tried %s", url); - return 0; + return -1; } close(local); @@ -296,11 +371,30 @@ int fetch(unsigned char *sha1) return 0; } +int fetch(unsigned char *sha1) +{ + struct alt_base *altbase = alt; + while (altbase) { + if (!fetch_object(altbase, sha1)) + return 0; + if (!fetch_pack(altbase, sha1)) + return 0; + if (fetch_alternates(altbase->base) > 0) { + altbase = alt; + continue; + } + altbase = altbase->next; + } + return error("Unable to find %s under %s\n", sha1_to_hex(sha1), + initial_base); +} + int fetch_ref(char *ref, unsigned char *sha1) { char *url, *posn; char hex[42]; struct buffer buffer; + char *base = initial_base; buffer.size = 41; buffer.posn = 0; buffer.buffer = hex; @@ -368,7 +462,12 @@ int main(int argc, char **argv) curl_easy_setopt(curl, CURLOPT_NETRC, CURL_NETRC_OPTIONAL); #endif - base = url; + alt = xmalloc(sizeof(*alt)); + alt->base = url; + alt->got_indices = 0; + alt->packs = NULL; + alt->next = NULL; + initial_base = url; if (pull(commit_id)) return 1; -- 2.30.2