http*: add helper methods for fetching objects (loose)

The code handling the fetching of loose objects in http-push.c and
http-walker.c have been refactored into new methods and a new struct
(object_http_request) in http.c. They are not meant to be invoked
elsewhere.

The new methods in http.c are
 - new_http_object_request
 - process_http_object_request
 - finish_http_object_request
 - abort_http_object_request
 - release_http_object_request

and the new struct is http_object_request.

RANGER_HEADER_SIZE and no_pragma_header is no longer made available
outside of http.c, since after the above changes, there are no other
instances of usage outside of http.c.

Remove members of the transfer_request struct in http-push.c and
http-walker.c, including filename, real_sha1 and zret, as they are used
no longer used.

Move the methods append_remote_object_url() and get_remote_object_url()
from http-push.c to http.c. Additionally, get_remote_object_url() is no
longer defined only when USE_CURL_MULTI is defined, since
non-USE_CURL_MULTI code in http.c uses it (namely, in
new_http_object_request()).

Refactor code from http-push.c::start_fetch_loose() and
http-walker.c::start_object_fetch_request() that deals with the details
of coming up with the filename to store the retrieved object, resuming
a previously aborted request, and making a new curl request, into a new
function, new_http_object_request().

Refactor code from http-walker.c::process_object_request() into the
function, process_http_object_request().

Refactor code from http-push.c::finish_request() and
http-walker.c::finish_object_request() into a new function,
finish_http_object_request(). It returns the result of the
move_temp_to_file() invocation.

Add a function, release_http_object_request(), which cleans up object
request data. http-push.c and http-walker.c invoke this function
separately; http-push.c::release_request() and
http-walker.c::release_object_request() do not invoke this function.

Add a function, abort_http_object_request(), which unlink()s the object
file and invokes release_http_object_request(). Update
http-walker.c::abort_object_request() to use this.

Signed-off-by: Tay Ray Chuan <rctay89@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/http-push.c b/http-push.c
index 8232cf488e39a126c532ba3475099bb018ee83e8..3439dcc5b89c6c4b056823634c43298a1ff3edc0 100644 (file)
--- a/http-push.c
+++ b/http-push.c
@@ -115,18 +115,10 @@ struct transfer_request
        struct remote_lock *lock;
        struct curl_slist *headers;
        struct buffer buffer;
-       char filename[PATH_MAX];
-       char tmpfile[PATH_MAX];
-       int local_fileno;
        enum transfer_state state;
        CURLcode curl_result;
        char errorstr[CURL_ERROR_SIZE];
        long http_code;
-       unsigned char real_sha1[20];
-       git_SHA_CTX c;
-       z_stream stream;
-       int zret;
-       int rename;
        void *userData;
        struct active_request_slot *slot;
        struct transfer_request *next;
@@ -232,15 +224,6 @@ static struct curl_slist *get_dav_token_headers(struct remote_lock *lock, enum d
        return dav_headers;
 }
 
-static void append_remote_object_url(struct strbuf *buf, const char *url,
-                                    const char *hex,
-                                    int only_two_digit_prefix)
-{
-       strbuf_addf(buf, "%sobjects/%.*s/", url, 2, hex);
-       if (!only_two_digit_prefix)
-               strbuf_addf(buf, "%s", hex+2);
-}
-
 static void finish_request(struct transfer_request *request);
 static void release_request(struct transfer_request *request);
 
@@ -254,169 +237,29 @@ static void process_response(void *callback_data)
 
 #ifdef USE_CURL_MULTI
 
-static char *get_remote_object_url(const char *url, const char *hex,
-                                  int only_two_digit_prefix)
-{
-       struct strbuf buf = STRBUF_INIT;
-       append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
-       return strbuf_detach(&buf, NULL);
-}
-
-static size_t fwrite_sha1_file(void *ptr, size_t eltsize, size_t nmemb,
-                              void *data)
-{
-       unsigned char expn[4096];
-       size_t size = eltsize * nmemb;
-       int posn = 0;
-       struct transfer_request *request = (struct transfer_request *)data;
-       do {
-               ssize_t retval = xwrite(request->local_fileno,
-                                       (char *) ptr + posn, size - posn);
-               if (retval < 0)
-                       return posn;
-               posn += retval;
-       } while (posn < size);
-
-       request->stream.avail_in = size;
-       request->stream.next_in = ptr;
-       do {
-               request->stream.next_out = expn;
-               request->stream.avail_out = sizeof(expn);
-               request->zret = git_inflate(&request->stream, Z_SYNC_FLUSH);
-               git_SHA1_Update(&request->c, expn,
-                               sizeof(expn) - request->stream.avail_out);
-       } while (request->stream.avail_in && request->zret == Z_OK);
-       data_received++;
-       return size;
-}
-
 static void start_fetch_loose(struct transfer_request *request)
 {
-       char *hex = sha1_to_hex(request->obj->sha1);
-       char *filename;
-       char prevfile[PATH_MAX];
-       char *url;
-       int prevlocal;
-       unsigned char prev_buf[PREV_BUF_SIZE];
-       ssize_t prev_read = 0;
-       long prev_posn = 0;
-       char range[RANGE_HEADER_SIZE];
-       struct curl_slist *range_header = NULL;
        struct active_request_slot *slot;
+       struct http_object_request *obj_req;
 
-       filename = sha1_file_name(request->obj->sha1);
-       snprintf(request->filename, sizeof(request->filename), "%s", filename);
-       snprintf(request->tmpfile, sizeof(request->tmpfile),
-                "%s.temp", filename);
-
-       snprintf(prevfile, sizeof(prevfile), "%s.prev", request->filename);
-       unlink_or_warn(prevfile);
-       rename(request->tmpfile, prevfile);
-       unlink_or_warn(request->tmpfile);
-
-       if (request->local_fileno != -1)
-               error("fd leakage in start: %d", request->local_fileno);
-       request->local_fileno = open(request->tmpfile,
-                                    O_WRONLY | O_CREAT | O_EXCL, 0666);
-       /*
-        * This could have failed due to the "lazy directory creation";
-        * try to mkdir the last path component.
-        */
-       if (request->local_fileno < 0 && errno == ENOENT) {
-               char *dir = strrchr(request->tmpfile, '/');
-               if (dir) {
-                       *dir = 0;
-                       mkdir(request->tmpfile, 0777);
-                       *dir = '/';
-               }
-               request->local_fileno = open(request->tmpfile,
-                                            O_WRONLY | O_CREAT | O_EXCL, 0666);
-       }
-
-       if (request->local_fileno < 0) {
+       obj_req = new_http_object_request(repo->url, request->obj->sha1);
+       if (obj_req == NULL) {
                request->state = ABORTED;
-               error("Couldn't create temporary file %s for %s: %s",
-                     request->tmpfile, request->filename, strerror(errno));
                return;
        }
 
-       memset(&request->stream, 0, sizeof(request->stream));
-
-       git_inflate_init(&request->stream);
-
-       git_SHA1_Init(&request->c);
-
-       url = get_remote_object_url(repo->url, hex, 0);
-       request->url = xstrdup(url);
-
-       /*
-        * If a previous temp file is present, process what was already
-        * fetched.
-        */
-       prevlocal = open(prevfile, O_RDONLY);
-       if (prevlocal != -1) {
-               do {
-                       prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
-                       if (prev_read>0) {
-                               if (fwrite_sha1_file(prev_buf,
-                                                    1,
-                                                    prev_read,
-                                                    request) == prev_read)
-                                       prev_posn += prev_read;
-                               else
-                                       prev_read = -1;
-                       }
-               } while (prev_read > 0);
-               close(prevlocal);
-       }
-       unlink_or_warn(prevfile);
-
-       /*
-        * Reset inflate/SHA1 if there was an error reading the previous temp
-        * file; also rewind to the beginning of the local file.
-        */
-       if (prev_read == -1) {
-               memset(&request->stream, 0, sizeof(request->stream));
-               git_inflate_init(&request->stream);
-               git_SHA1_Init(&request->c);
-               if (prev_posn>0) {
-                       prev_posn = 0;
-                       lseek(request->local_fileno, 0, SEEK_SET);
-                       ftruncate(request->local_fileno, 0);
-               }
-       }
-
-       slot = get_active_slot();
+       slot = obj_req->slot;
        slot->callback_func = process_response;
        slot->callback_data = request;
        request->slot = slot;
-
-       curl_easy_setopt(slot->curl, CURLOPT_FILE, request);
-       curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
-       curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, request->errorstr);
-       curl_easy_setopt(slot->curl, CURLOPT_URL, url);
-       curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
-
-       /*
-        * If we have successfully processed data from a previous fetch
-        * attempt, only fetch the data we don't already have.
-        */
-       if (prev_posn>0) {
-               if (push_verbosely)
-                       fprintf(stderr,
-                               "Resuming fetch of object %s at byte %ld\n",
-                               hex, prev_posn);
-               sprintf(range, "Range: bytes=%ld-", prev_posn);
-               range_header = curl_slist_append(range_header, range);
-               curl_easy_setopt(slot->curl,
-                                CURLOPT_HTTPHEADER, range_header);
-       }
+       request->userData = obj_req;
 
        /* Try to get the request started, abort the request on error */
        request->state = RUN_FETCH_LOOSE;
        if (!start_active_slot(slot)) {
                fprintf(stderr, "Unable to start GET request\n");
                repo->can_update_info_refs = 0;
+               release_http_object_request(obj_req);
                release_request(request);
        }
 }
@@ -675,16 +518,14 @@ static void release_request(struct transfer_request *request)
                        entry->next = entry->next->next;
        }
 
-       if (request->local_fileno != -1)
-               close(request->local_fileno);
        free(request->url);
        free(request);
 }
 
 static void finish_request(struct transfer_request *request)
 {
-       struct stat st;
        struct http_pack_request *preq;
+       struct http_object_request *obj_req;
 
        request->curl_result = request->slot->curl_result;
        request->http_code = request->slot->http_code;
@@ -739,39 +580,17 @@ static void finish_request(struct transfer_request *request)
                        aborted = 1;
                }
        } else if (request->state == RUN_FETCH_LOOSE) {
-               close(request->local_fileno);
-               request->local_fileno = -1;
-
-               if (request->curl_result != CURLE_OK &&
-                   request->http_code != 416) {
-                       if (stat(request->tmpfile, &st) == 0) {
-                               if (st.st_size == 0)
-                                       unlink_or_warn(request->tmpfile);
-                       }
-               } else {
-                       if (request->http_code == 416)
-                               warning("requested range invalid; we may already have all the data.");
-
-                       git_inflate_end(&request->stream);
-                       git_SHA1_Final(request->real_sha1, &request->c);
-                       if (request->zret != Z_STREAM_END) {
-                               unlink_or_warn(request->tmpfile);
-                       } else if (hashcmp(request->obj->sha1, request->real_sha1)) {
-                               unlink_or_warn(request->tmpfile);
-                       } else {
-                               request->rename =
-                                       move_temp_to_file(
-                                               request->tmpfile,
-                                               request->filename);
-                               if (request->rename == 0)
-                                       request->obj->flags |= (LOCAL | REMOTE);
-                       }
-               }
+               obj_req = (struct http_object_request *)request->userData;
+
+               if (finish_http_object_request(obj_req) == 0)
+                       if (obj_req->rename == 0)
+                               request->obj->flags |= (LOCAL | REMOTE);
 
                /* Try fetching packed if necessary */
-               if (request->obj->flags & LOCAL)
+               if (request->obj->flags & LOCAL) {
+                       release_http_object_request(obj_req);
                        release_request(request);
-               else
+               } else
                        start_fetch_packed(request);
 
        } else if (request->state == RUN_FETCH_PACKED) {
@@ -843,7 +662,6 @@ static void add_fetch_request(struct object *obj)
        request->url = NULL;
        request->lock = NULL;
        request->headers = NULL;
-       request->local_fileno = -1;
        request->state = NEED_FETCH;
        request->next = request_queue_head;
        request_queue_head = request;
@@ -882,7 +700,6 @@ static int add_send_request(struct object *obj, struct remote_lock *lock)
        request->url = NULL;
        request->lock = lock;
        request->headers = NULL;
-       request->local_fileno = -1;
        request->state = NEED_PUSH;
        request->next = request_queue_head;
        request_queue_head = request;

diff --git a/http-walker.c b/http-walker.c
index 8f7a975f96334ed59c1df9f4c9d4d01edc05a63c..700bc13112d65dfe8cf89af17522e28cf0d76e26 100644 (file)
--- a/http-walker.c
+++ b/http-walker.c
@@ -3,8 +3,6 @@
 #include "walker.h"
 #include "http.h"
 
-#define PREV_BUF_SIZE 4096
-
 struct alt_base
 {
        char *base;
@@ -25,20 +23,8 @@ struct object_request
        struct walker *walker;
        unsigned char sha1[20];
        struct alt_base *repo;
-       char *url;
-       char filename[PATH_MAX];
-       char tmpfile[PATH_MAX];
-       int local;
        enum object_request_state state;
-       CURLcode curl_result;
-       char errorstr[CURL_ERROR_SIZE];
-       long http_code;
-       unsigned char real_sha1[20];
-       git_SHA_CTX c;
-       z_stream stream;
-       int zret;
-       int rename;
-       struct active_request_slot *slot;
+       struct http_object_request *req;
        struct object_request *next;
 };
 
@@ -59,34 +45,6 @@ struct walker_data {
 
 static struct object_request *object_queue_head;
 
-static size_t fwrite_sha1_file(void *ptr, size_t eltsize, size_t nmemb,
-                              void *data)
-{
-       unsigned char expn[4096];
-       size_t size = eltsize * nmemb;
-       int posn = 0;
-       struct object_request *obj_req = (struct object_request *)data;
-       do {
-               ssize_t retval = xwrite(obj_req->local,
-                                       (char *) ptr + posn, size - posn);
-               if (retval < 0)
-                       return posn;
-               posn += retval;
-       } while (posn < size);
-
-       obj_req->stream.avail_in = size;
-       obj_req->stream.next_in = ptr;
-       do {
-               obj_req->stream.next_out = expn;
-               obj_req->stream.avail_out = sizeof(expn);
-               obj_req->zret = git_inflate(&obj_req->stream, Z_SYNC_FLUSH);
-               git_SHA1_Update(&obj_req->c, expn,
-                               sizeof(expn) - obj_req->stream.avail_out);
-       } while (obj_req->stream.avail_in && obj_req->zret == Z_OK);
-       data_received++;
-       return size;
-}
-
 static void fetch_alternates(struct walker *walker, const char *base);
 
 static void process_object_response(void *callback_data);
@@ -94,172 +52,35 @@ static void process_object_response(void *callback_data);
 static void start_object_request(struct walker *walker,
                                 struct object_request *obj_req)
 {
-       char *hex = sha1_to_hex(obj_req->sha1);
-       char prevfile[PATH_MAX];
-       char *url;
-       char *posn;
-       int prevlocal;
-       unsigned char prev_buf[PREV_BUF_SIZE];
-       ssize_t prev_read = 0;
-       long prev_posn = 0;
-       char range[RANGE_HEADER_SIZE];
-       struct curl_slist *range_header = NULL;
        struct active_request_slot *slot;
+       struct http_object_request *req;
 
-       snprintf(prevfile, sizeof(prevfile), "%s.prev", obj_req->filename);
-       unlink_or_warn(prevfile);
-       rename(obj_req->tmpfile, prevfile);
-       unlink_or_warn(obj_req->tmpfile);
-
-       if (obj_req->local != -1)
-               error("fd leakage in start: %d", obj_req->local);
-       obj_req->local = open(obj_req->tmpfile,
-                             O_WRONLY | O_CREAT | O_EXCL, 0666);
-       /*
-        * This could have failed due to the "lazy directory creation";
-        * try to mkdir the last path component.
-        */
-       if (obj_req->local < 0 && errno == ENOENT) {
-               char *dir = strrchr(obj_req->tmpfile, '/');
-               if (dir) {
-                       *dir = 0;
-                       mkdir(obj_req->tmpfile, 0777);
-                       *dir = '/';
-               }
-               obj_req->local = open(obj_req->tmpfile,
-                                     O_WRONLY | O_CREAT | O_EXCL, 0666);
-       }
-
-       if (obj_req->local < 0) {
+       req = new_http_object_request(obj_req->repo->base, obj_req->sha1);
+       if (req == NULL) {
                obj_req->state = ABORTED;
-               error("Couldn't create temporary file %s for %s: %s",
-                     obj_req->tmpfile, obj_req->filename, strerror(errno));
                return;
        }
+       obj_req->req = req;
 
-       memset(&obj_req->stream, 0, sizeof(obj_req->stream));
-
-       git_inflate_init(&obj_req->stream);
-
-       git_SHA1_Init(&obj_req->c);
-
-       url = xmalloc(strlen(obj_req->repo->base) + 51);
-       obj_req->url = xmalloc(strlen(obj_req->repo->base) + 51);
-       strcpy(url, obj_req->repo->base);
-       posn = url + strlen(obj_req->repo->base);
-       strcpy(posn, "/objects/");
-       posn += 9;
-       memcpy(posn, hex, 2);
-       posn += 2;
-       *(posn++) = '/';
-       strcpy(posn, hex + 2);
-       strcpy(obj_req->url, url);
-
-       /*
-        * If a previous temp file is present, process what was already
-        * fetched.
-        */
-       prevlocal = open(prevfile, O_RDONLY);
-       if (prevlocal != -1) {
-               do {
-                       prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
-                       if (prev_read>0) {
-                               if (fwrite_sha1_file(prev_buf,
-                                                    1,
-                                                    prev_read,
-                                                    obj_req) == prev_read)
-                                       prev_posn += prev_read;
-                               else
-                                       prev_read = -1;
-                       }
-               } while (prev_read > 0);
-               close(prevlocal);
-       }
-       unlink_or_warn(prevfile);
-
-       /*
-        * Reset inflate/SHA1 if there was an error reading the previous temp
-        * file; also rewind to the beginning of the local file.
-        */
-       if (prev_read == -1) {
-               memset(&obj_req->stream, 0, sizeof(obj_req->stream));
-               git_inflate_init(&obj_req->stream);
-               git_SHA1_Init(&obj_req->c);
-               if (prev_posn>0) {
-                       prev_posn = 0;
-                       lseek(obj_req->local, 0, SEEK_SET);
-                       ftruncate(obj_req->local, 0);
-               }
-       }
-
-       slot = get_active_slot();
+       slot = req->slot;
        slot->callback_func = process_object_response;
        slot->callback_data = obj_req;
-       obj_req->slot = slot;
-
-       curl_easy_setopt(slot->curl, CURLOPT_FILE, obj_req);
-       curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
-       curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, obj_req->errorstr);
-       curl_easy_setopt(slot->curl, CURLOPT_URL, url);
-       curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
-
-       /*
-        * If we have successfully processed data from a previous fetch
-        * attempt, only fetch the data we don't already have.
-        */
-       if (prev_posn>0) {
-               if (walker->get_verbosely)
-                       fprintf(stderr,
-                               "Resuming fetch of object %s at byte %ld\n",
-                               hex, prev_posn);
-               sprintf(range, "Range: bytes=%ld-", prev_posn);
-               range_header = curl_slist_append(range_header, range);
-               curl_easy_setopt(slot->curl,
-                                CURLOPT_HTTPHEADER, range_header);
-       }
 
        /* Try to get the request started, abort the request on error */
        obj_req->state = ACTIVE;
        if (!start_active_slot(slot)) {
                obj_req->state = ABORTED;
-               obj_req->slot = NULL;
-               close(obj_req->local);
-               obj_req->local = -1;
-               free(obj_req->url);
+               release_http_object_request(req);
                return;
        }
 }
 
 static void finish_object_request(struct object_request *obj_req)
 {
-       struct stat st;
-
-       close(obj_req->local);
-       obj_req->local = -1;
-
-       if (obj_req->http_code == 416) {
-               fprintf(stderr, "Warning: requested range invalid; we may already have all the data.\n");
-       } else if (obj_req->curl_result != CURLE_OK) {
-               if (stat(obj_req->tmpfile, &st) == 0)
-                       if (st.st_size == 0)
-                               unlink_or_warn(obj_req->tmpfile);
+       if (finish_http_object_request(obj_req->req))
                return;
-       }
-
-       git_inflate_end(&obj_req->stream);
-       git_SHA1_Final(obj_req->real_sha1, &obj_req->c);
-       if (obj_req->zret != Z_STREAM_END) {
-               unlink_or_warn(obj_req->tmpfile);
-               return;
-       }
-       if (hashcmp(obj_req->sha1, obj_req->real_sha1)) {
-               unlink_or_warn(obj_req->tmpfile);
-               return;
-       }
-       obj_req->rename =
-               move_temp_to_file(obj_req->tmpfile, obj_req->filename);
 
-       if (obj_req->rename == 0)
+       if (obj_req->req->rename == 0)
                walker_say(obj_req->walker, "got %s\n", sha1_to_hex(obj_req->sha1));
 }
 
@@ -271,19 +92,16 @@ static void process_object_response(void *callback_data)
        struct walker_data *data = walker->data;
        struct alt_base *alt = data->alt;
 
-       obj_req->curl_result = obj_req->slot->curl_result;
-       obj_req->http_code = obj_req->slot->http_code;
-       obj_req->slot = NULL;
+       process_http_object_request(obj_req->req);
        obj_req->state = COMPLETE;
 
        /* Use alternates if necessary */
-       if (missing_target(obj_req)) {
+       if (missing_target(obj_req->req)) {
                fetch_alternates(walker, alt->base);
                if (obj_req->repo->next != NULL) {
                        obj_req->repo =
                                obj_req->repo->next;
-                       close(obj_req->local);
-                       obj_req->local = -1;
+                       release_http_object_request(obj_req->req);
                        start_object_request(walker, obj_req);
                        return;
                }
@@ -296,8 +114,8 @@ static void release_object_request(struct object_request *obj_req)
 {
        struct object_request *entry = object_queue_head;
 
-       if (obj_req->local != -1)
-               error("fd leakage in release: %d", obj_req->local);
+       if (obj_req->req !=NULL && obj_req->req->localfile != -1)
+               error("fd leakage in release: %d", obj_req->req->localfile);
        if (obj_req == object_queue_head) {
                object_queue_head = obj_req->next;
        } else {
@@ -307,7 +125,6 @@ static void release_object_request(struct object_request *obj_req)
                        entry->next = entry->next->next;
        }
 
-       free(obj_req->url);
        free(obj_req);
 }
 
@@ -335,19 +152,13 @@ static void prefetch(struct walker *walker, unsigned char *sha1)
        struct object_request *newreq;
        struct object_request *tail;
        struct walker_data *data = walker->data;
-       char *filename = sha1_file_name(sha1);
 
        newreq = xmalloc(sizeof(*newreq));
        newreq->walker = walker;
        hashcpy(newreq->sha1, sha1);
        newreq->repo = data->alt;
-       newreq->url = NULL;
-       newreq->local = -1;
        newreq->state = WAITING;
-       snprintf(newreq->filename, sizeof(newreq->filename), "%s", filename);
-       snprintf(newreq->tmpfile, sizeof(newreq->tmpfile),
-                "%s.temp", filename);
-       newreq->slot = NULL;
+       newreq->req = NULL;
        newreq->next = NULL;
 
        http_is_verbose = walker->get_verbosely;
@@ -638,15 +449,6 @@ abort:
 
 static void abort_object_request(struct object_request *obj_req)
 {
-       if (obj_req->local >= 0) {
-               close(obj_req->local);
-               obj_req->local = -1;
-       }
-       unlink_or_warn(obj_req->tmpfile);
-       if (obj_req->slot) {
-               release_active_slot(obj_req->slot);
-               obj_req->slot = NULL;
-       }
        release_object_request(obj_req);
 }
 
@@ -655,6 +457,7 @@ static int fetch_object(struct walker *walker, struct alt_base *repo, unsigned c
        char *hex = sha1_to_hex(sha1);
        int ret = 0;
        struct object_request *obj_req = object_queue_head;
+       struct http_object_request *req;
 
        while (obj_req != NULL && hashcmp(obj_req->sha1, sha1))
                obj_req = obj_req->next;
@@ -662,6 +465,8 @@ static int fetch_object(struct walker *walker, struct alt_base *repo, unsigned c
                return error("Couldn't find request for %s in the queue", hex);
 
        if (has_sha1_file(obj_req->sha1)) {
+               if (obj_req->req != NULL)
+                       abort_http_object_request(obj_req->req);
                abort_object_request(obj_req);
                return 0;
        }
@@ -673,34 +478,42 @@ static int fetch_object(struct walker *walker, struct alt_base *repo, unsigned c
        start_object_request(walker, obj_req);
 #endif
 
+       /*
+        * obj_req->req might change when fetching alternates in the callback
+        * process_object_response; therefore, the "shortcut" variable, req,
+        * is used only after we're done with slots.
+        */
        while (obj_req->state == ACTIVE)
-               run_active_slot(obj_req->slot);
+               run_active_slot(obj_req->req->slot);
+
+       req = obj_req->req;
 
-       if (obj_req->local != -1) {
-               close(obj_req->local);
-               obj_req->local = -1;
+       if (req->localfile != -1) {
+               close(req->localfile);
+               req->localfile = -1;
        }
 
        if (obj_req->state == ABORTED) {
                ret = error("Request for %s aborted", hex);
-       } else if (obj_req->curl_result != CURLE_OK &&
-                  obj_req->http_code != 416) {
-               if (missing_target(obj_req))
+       } else if (req->curl_result != CURLE_OK &&
+                  req->http_code != 416) {
+               if (missing_target(req))
                        ret = -1; /* Be silent, it is probably in a pack. */
                else
                        ret = error("%s (curl_result = %d, http_code = %ld, sha1 = %s)",
-                                   obj_req->errorstr, obj_req->curl_result,
-                                   obj_req->http_code, hex);
-       } else if (obj_req->zret != Z_STREAM_END) {
+                                   req->errorstr, req->curl_result,
+                                   req->http_code, hex);
+       } else if (req->zret != Z_STREAM_END) {
                walker->corrupt_object_found++;
-               ret = error("File %s (%s) corrupt", hex, obj_req->url);
-       } else if (hashcmp(obj_req->sha1, obj_req->real_sha1)) {
+               ret = error("File %s (%s) corrupt", hex, req->url);
+       } else if (hashcmp(obj_req->sha1, req->real_sha1)) {
                ret = error("File %s has bad hash", hex);
-       } else if (obj_req->rename < 0) {
+       } else if (req->rename < 0) {
                ret = error("unable to write sha1 filename %s",
-                           obj_req->filename);
+                           req->filename);
        }
 
+       release_http_object_request(req);
        release_object_request(obj_req);
        return ret;
 }

diff --git a/http.c b/http.c
index 381593441e67ac542d9b08e15fea0d81629df119..95b2137cfbb1eef355c392e7634e1c761de27379 100644 (file)
--- a/http.c
+++ b/http.c
@@ -12,6 +12,10 @@ static CURLM *curlm;
 #ifndef NO_CURL_EASY_DUPHANDLE
 static CURL *curl_default;
 #endif
+
+#define PREV_BUF_SIZE 4096
+#define RANGE_HEADER_SIZE 30
+
 char curl_errorstr[CURL_ERROR_SIZE];
 
 static int curl_ssl_verify = -1;
@@ -30,8 +34,7 @@ static const char *curl_http_proxy;
 static char *user_name, *user_pass;
 
 static struct curl_slist *pragma_header;
-
-struct curl_slist *no_pragma_header;
+static struct curl_slist *no_pragma_header;
 
 static struct active_request_slot *active_queue_head;
 
@@ -666,6 +669,23 @@ static char *quote_ref_url(const char *base, const char *ref)
        return strbuf_detach(&buf, NULL);
 }
 
+void append_remote_object_url(struct strbuf *buf, const char *url,
+                             const char *hex,
+                             int only_two_digit_prefix)
+{
+       strbuf_addf(buf, "%s/objects/%.*s/", url, 2, hex);
+       if (!only_two_digit_prefix)
+               strbuf_addf(buf, "%s", hex+2);
+}
+
+char *get_remote_object_url(const char *url, const char *hex,
+                           int only_two_digit_prefix)
+{
+       struct strbuf buf = STRBUF_INIT;
+       append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
+       return strbuf_detach(&buf, NULL);
+}
+
 /* http_request() targets */
 #define HTTP_REQUEST_STRBUF    0
 #define HTTP_REQUEST_FILE      1
@@ -995,3 +1015,229 @@ abort:
        free(filename);
        return NULL;
 }
+
+/* Helpers for fetching objects (loose) */
+static size_t fwrite_sha1_file(void *ptr, size_t eltsize, size_t nmemb,
+                              void *data)
+{
+       unsigned char expn[4096];
+       size_t size = eltsize * nmemb;
+       int posn = 0;
+       struct http_object_request *freq =
+               (struct http_object_request *)data;
+       do {
+               ssize_t retval = xwrite(freq->localfile,
+                                       (char *) ptr + posn, size - posn);
+               if (retval < 0)
+                       return posn;
+               posn += retval;
+       } while (posn < size);
+
+       freq->stream.avail_in = size;
+       freq->stream.next_in = ptr;
+       do {
+               freq->stream.next_out = expn;
+               freq->stream.avail_out = sizeof(expn);
+               freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
+               git_SHA1_Update(&freq->c, expn,
+                               sizeof(expn) - freq->stream.avail_out);
+       } while (freq->stream.avail_in && freq->zret == Z_OK);
+       data_received++;
+       return size;
+}
+
+struct http_object_request *new_http_object_request(const char *base_url,
+       unsigned char *sha1)
+{
+       char *hex = sha1_to_hex(sha1);
+       char *filename;
+       char prevfile[PATH_MAX];
+       char *url;
+       int prevlocal;
+       unsigned char prev_buf[PREV_BUF_SIZE];
+       ssize_t prev_read = 0;
+       long prev_posn = 0;
+       char range[RANGE_HEADER_SIZE];
+       struct curl_slist *range_header = NULL;
+       struct http_object_request *freq;
+
+       freq = xmalloc(sizeof(*freq));
+       hashcpy(freq->sha1, sha1);
+       freq->localfile = -1;
+
+       filename = sha1_file_name(sha1);
+       snprintf(freq->filename, sizeof(freq->filename), "%s", filename);
+       snprintf(freq->tmpfile, sizeof(freq->tmpfile),
+                "%s.temp", filename);
+
+       snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
+       unlink_or_warn(prevfile);
+       rename(freq->tmpfile, prevfile);
+       unlink_or_warn(freq->tmpfile);
+
+       if (freq->localfile != -1)
+               error("fd leakage in start: %d", freq->localfile);
+       freq->localfile = open(freq->tmpfile,
+                              O_WRONLY | O_CREAT | O_EXCL, 0666);
+       /*
+        * This could have failed due to the "lazy directory creation";
+        * try to mkdir the last path component.
+        */
+       if (freq->localfile < 0 && errno == ENOENT) {
+               char *dir = strrchr(freq->tmpfile, '/');
+               if (dir) {
+                       *dir = 0;
+                       mkdir(freq->tmpfile, 0777);
+                       *dir = '/';
+               }
+               freq->localfile = open(freq->tmpfile,
+                                      O_WRONLY | O_CREAT | O_EXCL, 0666);
+       }
+
+       if (freq->localfile < 0) {
+               error("Couldn't create temporary file %s for %s: %s",
+                     freq->tmpfile, freq->filename, strerror(errno));
+               goto abort;
+       }
+
+       memset(&freq->stream, 0, sizeof(freq->stream));
+
+       git_inflate_init(&freq->stream);
+
+       git_SHA1_Init(&freq->c);
+
+       url = get_remote_object_url(base_url, hex, 0);
+       freq->url = xstrdup(url);
+
+       /*
+        * If a previous temp file is present, process what was already
+        * fetched.
+        */
+       prevlocal = open(prevfile, O_RDONLY);
+       if (prevlocal != -1) {
+               do {
+                       prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
+                       if (prev_read>0) {
+                               if (fwrite_sha1_file(prev_buf,
+                                                    1,
+                                                    prev_read,
+                                                    freq) == prev_read) {
+                                       prev_posn += prev_read;
+                               } else {
+                                       prev_read = -1;
+                               }
+                       }
+               } while (prev_read > 0);
+               close(prevlocal);
+       }
+       unlink_or_warn(prevfile);
+
+       /*
+        * Reset inflate/SHA1 if there was an error reading the previous temp
+        * file; also rewind to the beginning of the local file.
+        */
+       if (prev_read == -1) {
+               memset(&freq->stream, 0, sizeof(freq->stream));
+               git_inflate_init(&freq->stream);
+               git_SHA1_Init(&freq->c);
+               if (prev_posn>0) {
+                       prev_posn = 0;
+                       lseek(freq->localfile, 0, SEEK_SET);
+                       ftruncate(freq->localfile, 0);
+               }
+       }
+
+       freq->slot = get_active_slot();
+
+       curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
+       curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
+       curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
+       curl_easy_setopt(freq->slot->curl, CURLOPT_URL, url);
+       curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
+
+       /*
+        * If we have successfully processed data from a previous fetch
+        * attempt, only fetch the data we don't already have.
+        */
+       if (prev_posn>0) {
+               if (http_is_verbose)
+                       fprintf(stderr,
+                               "Resuming fetch of object %s at byte %ld\n",
+                               hex, prev_posn);
+               sprintf(range, "Range: bytes=%ld-", prev_posn);
+               range_header = curl_slist_append(range_header, range);
+               curl_easy_setopt(freq->slot->curl,
+                                CURLOPT_HTTPHEADER, range_header);
+       }
+
+       return freq;
+
+       free(url);
+abort:
+       free(filename);
+       free(freq);
+       return NULL;
+}
+
+void process_http_object_request(struct http_object_request *freq)
+{
+       if (freq->slot == NULL)
+               return;
+       freq->curl_result = freq->slot->curl_result;
+       freq->http_code = freq->slot->http_code;
+       freq->slot = NULL;
+}
+
+int finish_http_object_request(struct http_object_request *freq)
+{
+       struct stat st;
+
+       close(freq->localfile);
+       freq->localfile = -1;
+
+       process_http_object_request(freq);
+
+       if (freq->http_code == 416) {
+               fprintf(stderr, "Warning: requested range invalid; we may already have all the data.\n");
+       } else if (freq->curl_result != CURLE_OK) {
+               if (stat(freq->tmpfile, &st) == 0)
+                       if (st.st_size == 0)
+                               unlink_or_warn(freq->tmpfile);
+               return -1;
+       }
+
+       git_inflate_end(&freq->stream);
+       git_SHA1_Final(freq->real_sha1, &freq->c);
+       if (freq->zret != Z_STREAM_END) {
+               unlink_or_warn(freq->tmpfile);
+               return -1;
+       }
+       if (hashcmp(freq->sha1, freq->real_sha1)) {
+               unlink_or_warn(freq->tmpfile);
+               return -1;
+       }
+       freq->rename =
+               move_temp_to_file(freq->tmpfile, freq->filename);
+
+       return freq->rename;
+}
+
+void abort_http_object_request(struct http_object_request *freq)
+{
+       unlink_or_warn(freq->tmpfile);
+
+       release_http_object_request(freq);
+}
+
+void release_http_object_request(struct http_object_request *freq)
+{
+       if (freq->localfile != -1) {
+               close(freq->localfile);
+               freq->localfile = -1;
+       }
+       if (freq->url != NULL) {
+               free(freq->url);
+               freq->url = NULL;
+       }
+       freq->slot = NULL;
+}

diff --git a/http.h b/http.h
index 511c0c4417fed203068dbf5f45ac43a66fd9e0be..4c4e99c2f6cae97110efe28986333fc5cbc4c095 100644 (file)
--- a/http.h
+++ b/http.h
@@ -88,10 +88,6 @@ extern void add_fill_function(void *data, int (*fill)(void *));
 extern void step_active_slots(void);
 #endif
 
-extern struct curl_slist *no_pragma_header;
-
-#define RANGE_HEADER_SIZE 30
-
 extern void http_init(struct remote *remote);
 extern void http_cleanup(void);
 
@@ -114,6 +110,13 @@ static inline int missing__target(int code, int result)
 
 #define missing_target(a) missing__target((a)->http_code, (a)->curl_result)
 
+/* Helpers for modifying and creating URLs */
+extern void append_remote_object_url(struct strbuf *buf, const char *url,
+                                    const char *hex,
+                                    int only_two_digit_prefix);
+extern char *get_remote_object_url(const char *url, const char *hex,
+                                  int only_two_digit_prefix);
+
 /* Options for http_request_*() */
 #define HTTP_NO_CACHE          1
 
@@ -167,4 +170,30 @@ extern struct http_pack_request *new_http_pack_request(
 extern int finish_http_pack_request(struct http_pack_request *preq);
 extern void release_http_pack_request(struct http_pack_request *preq);
 
+/* Helpers for fetching object */
+struct http_object_request
+{
+       char *url;
+       char filename[PATH_MAX];
+       char tmpfile[PATH_MAX];
+       int localfile;
+       CURLcode curl_result;
+       char errorstr[CURL_ERROR_SIZE];
+       long http_code;
+       unsigned char sha1[20];
+       unsigned char real_sha1[20];
+       git_SHA_CTX c;
+       z_stream stream;
+       int zret;
+       int rename;
+       struct active_request_slot *slot;
+};
+
+extern struct http_object_request *new_http_object_request(
+       const char *base_url, unsigned char *sha1);
+extern void process_http_object_request(struct http_object_request *freq);
+extern int finish_http_object_request(struct http_object_request *freq);
+extern void abort_http_object_request(struct http_object_request *freq);
+extern void release_http_object_request(struct http_object_request *freq);
+
 #endif /* HTTP_H */