thodg/got/lib/fetch.c

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• Hash : 0e4002ca
  Author :
  Date : 2020-03-21T21:49:13
  

  add support for fetching arbitrary references to 'got clone' and 'got fetch'

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• lib/fetch.c

• /*
   * Copyright (c) 2018, 2019 Ori Bernstein <ori@openbsd.org>
   *
   * Permission to use, copy, modify, and distribute this software for any
   * purpose with or without fee is hereby granted, provided that the above
   * copyright notice and this permission notice appear in all copies.
   *
   * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
   * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
   * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
   * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
   * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
   */
  
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <sys/queue.h>
  #include <sys/uio.h>
  #include <sys/socket.h>
  #include <sys/wait.h>
  #include <sys/syslimits.h>
  #include <sys/resource.h>
  #include <sys/socket.h>
  
  #include <errno.h>
  #include <err.h>
  #include <fcntl.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <stdint.h>
  #include <sha1.h>
  #include <zlib.h>
  #include <ctype.h>
  #include <limits.h>
  #include <imsg.h>
  #include <time.h>
  #include <uuid.h>
  #include <netdb.h>
  #include <netinet/in.h>
  
  #include "got_error.h"
  #include "got_reference.h"
  #include "got_repository.h"
  #include "got_path.h"
  #include "got_cancel.h"
  #include "got_worktree.h"
  #include "got_object.h"
  #include "got_opentemp.h"
  #include "got_fetch.h"
  
  #include "got_lib_delta.h"
  #include "got_lib_inflate.h"
  #include "got_lib_object.h"
  #include "got_lib_object_parse.h"
  #include "got_lib_object_create.h"
  #include "got_lib_pack.h"
  #include "got_lib_sha1.h"
  #include "got_lib_privsep.h"
  #include "got_lib_object_cache.h"
  #include "got_lib_repository.h"
  
  #ifndef nitems
  #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
  #endif
  
  #ifndef MIN
  #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
  #endif
  
  static int
  hassuffix(char *base, char *suf)
  {
  	int nb, ns;
  
  	nb = strlen(base);
  	ns = strlen(suf);
  	if (ns <= nb && strcmp(base + (nb - ns), suf) == 0)
  		return 1;
  	return 0;
  }
  
  static const struct got_error *
  dial_ssh(pid_t *fetchpid, int *fetchfd, const char *host, const char *port,
      const char *path, const char *direction, int verbosity)
  {
  	const struct got_error *error = NULL;
  	int pid, pfd[2];
  	char cmd[64];
  	char *argv[11];
  	int i = 0;
  
  	*fetchpid = -1;
  	*fetchfd = -1;
  
  	if (port == NULL)
  		port = "22";
  
  	argv[0] = GOT_FETCH_PATH_SSH;
  	argv[1] = "-p";
  	argv[2] = (char *)port;
  	if (verbosity == -1) {
  		argv[3 + i++] = "-q";
  	} else {
  		/* ssh(1) allows up to 3 "-v" options. */
  		for (i = 0; i < MIN(3, verbosity); i++)
  			argv[3 + i] = "-v";
  	}
  	argv[3 + i] = "--";
  	argv[4 + i] = (char *)host;
  	argv[5 + i] = (char *)cmd;
  	argv[6 + i] = (char *)path;
  	argv[7 + i] = NULL;
  
  	if (pipe(pfd) == -1)
  		return got_error_from_errno("pipe");
  
  	pid = fork();
  	if (pid == -1) {
  		error = got_error_from_errno("fork");
  		close(pfd[0]);
  		close(pfd[1]);
  		return error;
  	} else if (pid == 0) {
  		int n;
  		close(pfd[1]);
  		dup2(pfd[0], 0);
  		dup2(pfd[0], 1);
  		n = snprintf(cmd, sizeof(cmd), "git-%s-pack", direction);
  		if (n < 0 || n >= sizeof(cmd))
  			err(1, "snprintf");
  		if (execv(GOT_FETCH_PATH_SSH, argv) == -1)
  			err(1, "execl");
  		abort(); /* not reached */
  	} else {
  		close(pfd[0]);
  		*fetchpid = pid;
  		*fetchfd = pfd[1];
  		return NULL;
  	}
  }
  
  static const struct got_error *
  dial_git(int *fetchfd, const char *host, const char *port, const char *path,
      const char *direction)
  {
  	const struct got_error *err = NULL;
  	struct addrinfo hints, *servinfo, *p;
  	char *cmd = NULL, *pkt = NULL;
  	int fd = -1, totlen, r, eaicode;
  
  	*fetchfd = -1;
  
  	if (port == NULL)
  		port = GOT_DEFAULT_GIT_PORT_STR;
  
  	memset(&hints, 0, sizeof hints);
  	hints.ai_family = AF_UNSPEC;
  	hints.ai_socktype = SOCK_STREAM;
  	eaicode = getaddrinfo(host, port, &hints, &servinfo);
  	if (eaicode) {
  		char msg[512];
  		snprintf(msg, sizeof(msg), "%s: %s", host,
  		    gai_strerror(eaicode));
  		return got_error_msg(GOT_ERR_ADDRINFO, msg);
  	}
  
  	for (p = servinfo; p != NULL; p = p->ai_next) {
  		if ((fd = socket(p->ai_family, p->ai_socktype,
  		    p->ai_protocol)) == -1)
  			continue;
  		if (connect(fd, p->ai_addr, p->ai_addrlen) == 0)
  			break;
  		err = got_error_from_errno("connect");
  		close(fd);
  	}
  	if (p == NULL)
  		goto done;
  
  	if (asprintf(&cmd, "git-%s-pack %s", direction, path) == -1) {
  		err = got_error_from_errno("asprintf");
  		goto done;
  	}
  	totlen = 4 + strlen(cmd) + 1 + strlen("host=") + strlen(host) + 1;
  	if (asprintf(&pkt, "%04x%s", totlen, cmd) == -1) {
  		err = got_error_from_errno("asprintf");
  		goto done;
  	}
  	r = write(fd, pkt, strlen(pkt) + 1);
  	if (r == -1) {
  		err = got_error_from_errno("write");
  		goto done;
  	}
  	if (asprintf(&pkt, "host=%s", host) == -1) {
  		err = got_error_from_errno("asprintf");
  		goto done;
  	}
  	r = write(fd, pkt, strlen(pkt) + 1);
  	if (r == -1) {
  		err = got_error_from_errno("write");
  		goto done;
  	}
  done:
  	free(cmd);
  	free(pkt);
  	if (err) {
  		if (fd != -1)
  			close(fd);
  	} else
  		*fetchfd = fd;
  	return err;
  }
  
  const struct got_error *
  got_fetch_connect(pid_t *fetchpid, int *fetchfd, const char *proto,
      const char *host, const char *port, const char *server_path, int verbosity)
  {
  	const struct got_error *err = NULL;
  
  	*fetchpid = -1;
  	*fetchfd = -1;
  
  	if (strcmp(proto, "ssh") == 0 || strcmp(proto, "git+ssh") == 0)
  		err = dial_ssh(fetchpid, fetchfd, host, port, server_path,
  		    "upload", verbosity);
  	else if (strcmp(proto, "git") == 0)
  		err = dial_git(fetchfd, host, port, server_path, "upload");
  	else if (strcmp(proto, "http") == 0 || strcmp(proto, "git+http") == 0)
  		err = got_error_path(proto, GOT_ERR_NOT_IMPL);
  	else
  		err = got_error_path(proto, GOT_ERR_BAD_PROTO);
  	return err;
  }
  
  const struct got_error *
  got_fetch_parse_uri(char **proto, char **host, char **port,
      char **server_path, char **repo_name, const char *uri)
  {
  	const struct got_error *err = NULL;
  	char *s, *p, *q;
  	int n;
  
  	*proto = *host = *port = *server_path = *repo_name = NULL;
  
  	p = strstr(uri, "://");
  	if (!p) {
  		/* Try parsing Git's "scp" style URL syntax. */
  		*proto = strdup("ssh");
  		if (proto == NULL) {
  			err = got_error_from_errno("strdup");
  			goto done;
  		}
  		s = (char *)uri;
  		q = strchr(s, ':');
  		if (q == NULL) {
  			err = got_error(GOT_ERR_PARSE_URI);
  			goto done;
  		}
  		/* No slashes allowed before first colon. */
  		p = strchr(s, '/');
  		if (p && q > p) {
  			err = got_error(GOT_ERR_PARSE_URI);
  			goto done;
  		}
  		*host = strndup(s, q - s);
  		if (*host == NULL) {
  			err = got_error_from_errno("strndup");
  			goto done;
  		}
  		p = q + 1;
  	} else {
  		*proto = strndup(uri, p - uri);
  		if (proto == NULL) {
  			err = got_error_from_errno("strndup");
  			goto done;
  		}
  		s = p + 3;
  
  		p = strstr(s, "/");
  		if (p == NULL || strlen(p) == 1) {
  			err = got_error(GOT_ERR_PARSE_URI);
  			goto done;
  		}
  
  		q = memchr(s, ':', p - s);
  		if (q) {
  			*host = strndup(s, q - s);
  			if (*host == NULL) {
  				err = got_error_from_errno("strndup");
  				goto done;
  			}
  			*port = strndup(q + 1, p - (q + 1));
  			if (*port == NULL) {
  				err = got_error_from_errno("strndup");
  				goto done;
  			}
  		} else {
  			*host = strndup(s, p - s);
  			if (*host == NULL) {
  				err = got_error_from_errno("strndup");
  				goto done;
  			}
  		}
  	}
  
  	*server_path = strdup(p);
  	if (*server_path == NULL) {
  		err = got_error_from_errno("strdup");
  		goto done;
  	}
  
  	p = strrchr(p, '/');
  	if (!p || strlen(p) <= 1) {
  		err = got_error(GOT_ERR_PARSE_URI);
  		goto done;
  	}
  	p++;
  	n = strlen(p);
  	if (n == 0) {
  		err = got_error(GOT_ERR_PARSE_URI);
  		goto done;
  	}
  	if (hassuffix(p, ".git"))
  		n -= 4;
  	*repo_name = strndup(p, (p + n) - p);
  	if (*repo_name == NULL) {
  		err = got_error_from_errno("strndup");
  		goto done;
  	}
  done:
  	if (err) {
  		free(*proto);
  		*proto = NULL;
  		free(*host);
  		*host = NULL;
  		free(*port);
  		*port = NULL;
  		free(*server_path);
  		*server_path = NULL;
  		free(*repo_name);
  		*repo_name = NULL;
  	}
  	return err;
  }
  
  static const struct got_error *
  check_pack_hash(int fd, size_t sz, uint8_t *hcomp)
  {
  	SHA1_CTX ctx;
  	uint8_t hexpect[SHA1_DIGEST_LENGTH];
  	uint8_t buf[32 * 1024];
  	ssize_t n, r, nr;
  
  	if (sz < sizeof(struct got_packfile_hdr) + SHA1_DIGEST_LENGTH)
  		return got_error_msg(GOT_ERR_BAD_PACKFILE, "short packfile");
  
  	n = 0;
  	SHA1Init(&ctx);
  	while (n < sz - 20) {
  		nr = sizeof(buf);
  		if (sz - n - 20 < sizeof(buf))
  			nr = sz - n - 20;
  		r = read(fd, buf, nr);
  		if (r == -1)
  			return got_error_from_errno("read");
  		if (r != nr)
  			return got_error_msg(GOT_ERR_BAD_PACKFILE,
  			    "short pack file");
  		SHA1Update(&ctx, buf, nr);
  		n += r;
  	}
  	SHA1Final(hcomp, &ctx);
  
  	r = read(fd, hexpect, sizeof(hexpect));
  	if (r == -1)
  		return got_error_from_errno("read");
  	if (r != sizeof(hexpect))
  		return got_error_msg(GOT_ERR_BAD_PACKFILE,
  		    "short pack file");
  
  	if (memcmp(hcomp, hexpect, SHA1_DIGEST_LENGTH) != 0)
  		return got_error_msg(GOT_ERR_BAD_PACKFILE,
  		    "packfile checksum mismatch");
  
  	return NULL;
  }
  
  const struct got_error*
  got_fetch_pack(struct got_object_id **pack_hash, struct got_pathlist_head *refs,
      struct got_pathlist_head *symrefs, const char *remote_name,
      int mirror_references, int fetch_all_branches,
      struct got_pathlist_head *wanted_branches,
      struct got_pathlist_head *wanted_refs, int list_refs_only, int verbosity,
      int fetchfd, struct got_repository *repo,
      got_fetch_progress_cb progress_cb, void *progress_arg)
  {
  	int imsg_fetchfds[2], imsg_idxfds[2];
  	int packfd = -1, npackfd = -1, idxfd = -1, nidxfd = -1, nfetchfd = -1;
  	int tmpfds[3], i;
  	int fetchstatus, idxstatus, done = 0;
  	const struct got_error *err;
  	struct imsgbuf fetchibuf, idxibuf;
  	pid_t fetchpid, idxpid;
  	char *tmppackpath = NULL, *tmpidxpath = NULL;
  	char *packpath = NULL, *idxpath = NULL, *id_str = NULL;
  	const char *repo_path = NULL;
  	struct got_pathlist_head have_refs;
  	struct got_pathlist_entry *pe;
  	struct got_reflist_head my_refs;
  	struct got_reflist_entry *re;
  	off_t packfile_size = 0;
  	struct got_packfile_hdr pack_hdr;
  	uint32_t nobj = 0;
  	char *ref_prefix = NULL;
  	size_t ref_prefixlen = 0;
  	char *path;
  	char *progress = NULL;
  
  	/*
  	 * Prevent fetching of references that won't make any
  	 * sense outside of the remote repository's context.
  	 */
  	TAILQ_FOREACH(pe, wanted_refs, entry) {
  		const char *refname = pe->path;
  		if (strncmp(refname, "refs/got/", 9) == 0 ||
  		    strncmp(refname, "got/", 4) == 0 ||
  		    strncmp(refname, "refs/remotes/", 13) == 0 ||
  		    strncmp(refname, "remotes/", 8) == 0)
  			return got_error_path(refname, GOT_ERR_FETCH_BAD_REF);
  	}
  
  	if (!list_refs_only)
  		repo_path = got_repo_get_path_git_dir(repo);
  
  	*pack_hash = NULL;
  	for (i = 0; i < nitems(tmpfds); i++)
  		tmpfds[i] = -1;
  
  	TAILQ_INIT(&have_refs);
  	SIMPLEQ_INIT(&my_refs);
  
  	if (!mirror_references) {
  		if (asprintf(&ref_prefix, "refs/remotes/%s/",
  		    remote_name) == -1)
  			return got_error_from_errno("asprintf");
  		ref_prefixlen = strlen(ref_prefix);
  	}
  
  	if (!list_refs_only) {
  		err = got_ref_list(&my_refs, repo, NULL,
  		    got_ref_cmp_by_name, NULL);
  		if (err)
  			goto done;
  	}
  
  	SIMPLEQ_FOREACH(re, &my_refs, entry) {
  		struct got_object_id *id;
  		const char *refname;
  
  		if (got_ref_is_symbolic(re->ref))
  			continue;
  
  		refname = got_ref_get_name(re->ref);
  
  		if (mirror_references) {
  			char *name;
  			err = got_ref_resolve(&id, repo, re->ref);
  			if (err)
  				goto done;
  			name = strdup(refname);
  			if (name == NULL) {
  				err = got_error_from_errno("strdup");
  				goto done;
  			}
  			err = got_pathlist_append(&have_refs, name, id);
  			if (err)
  				goto done;
  			continue;
  		}
  
  		if (strncmp("refs/tags/", refname, 10) == 0) {
  			char *tagname;
  
  			err = got_ref_resolve(&id, repo, re->ref);
  			if (err)
  				goto done;
  			tagname = strdup(refname);
  			if (tagname == NULL) {
  				err = got_error_from_errno("strdup");
  				goto done;
  			}
  			err = got_pathlist_append(&have_refs, tagname, id);
  			if (err) {
  				free(tagname);
  				goto done;
  			}
  		}
  
  		if (strncmp(ref_prefix, refname, ref_prefixlen) == 0) {
  			char *branchname;
  
  			err = got_ref_resolve(&id, repo, re->ref);
  			if (err)
  				goto done;
  
  			if (asprintf(&branchname, "refs/heads/%s",
  			    refname + ref_prefixlen) == -1) {
  				err = got_error_from_errno("asprintf");
  				goto done;
  			}
  			err = got_pathlist_append(&have_refs, branchname, id);
  			if (err) {
  				free(branchname);
  				goto done;
  			}
  		}
  	}
  
  	if (list_refs_only) {
  		packfd = got_opentempfd();
  		if (packfd == -1) {
  			err = got_error_from_errno("got_opentempfd");
  			goto done;
  		}
  	} else {
  		if (asprintf(&path, "%s/%s/fetching.pack",
  		    repo_path, GOT_OBJECTS_PACK_DIR) == -1) {
  			err = got_error_from_errno("asprintf");
  			goto done;
  		}
  		err = got_opentemp_named_fd(&tmppackpath, &packfd, path);
  		free(path);
  		if (err)
  			goto done;
  	}
  	if (list_refs_only) {
  		idxfd = got_opentempfd();
  		if (idxfd == -1) {
  			err = got_error_from_errno("got_opentempfd");
  			goto done;
  		}
  	} else {
  		if (asprintf(&path, "%s/%s/fetching.idx",
  		    repo_path, GOT_OBJECTS_PACK_DIR) == -1) {
  			err = got_error_from_errno("asprintf");
  			goto done;
  		}
  		err = got_opentemp_named_fd(&tmpidxpath, &idxfd, path);
  		free(path);
  		if (err)
  			goto done;
  	}
  	nidxfd = dup(idxfd);
  	if (nidxfd == -1) {
  		err = got_error_from_errno("dup");
  		goto done;
  	}
  
  	for (i = 0; i < nitems(tmpfds); i++) {
  		tmpfds[i] = got_opentempfd();
  		if (tmpfds[i] == -1) {
  			err = got_error_from_errno("got_opentempfd");
  			goto done;
  		}
  	}
  
  	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fetchfds) == -1) {
  		err = got_error_from_errno("socketpair");
  		goto done;
  	}
  
  	fetchpid = fork();
  	if (fetchpid == -1) {
  		err = got_error_from_errno("fork");
  		goto done;
  	} else if (fetchpid == 0){
  		got_privsep_exec_child(imsg_fetchfds,
  		    GOT_PATH_PROG_FETCH_PACK, tmppackpath);
  	}
  
  	if (close(imsg_fetchfds[1]) != 0) {
  		err = got_error_from_errno("close");
  		goto done;
  	}
  	imsg_init(&fetchibuf, imsg_fetchfds[0]);
  	nfetchfd = dup(fetchfd);
  	if (nfetchfd == -1) {
  		err = got_error_from_errno("dup");
  		goto done;
  	}
  	err = got_privsep_send_fetch_req(&fetchibuf, nfetchfd, &have_refs,
  	    fetch_all_branches, wanted_branches, wanted_refs,
  	    list_refs_only, verbosity);
  	if (err != NULL)
  		goto done;
  	nfetchfd = -1;
  	npackfd = dup(packfd);
  	if (npackfd == -1) {
  		err = got_error_from_errno("dup");
  		goto done;
  	}
  	err = got_privsep_send_fetch_outfd(&fetchibuf, npackfd);
  	if (err != NULL)
  		goto done;
  	npackfd = -1;
  
  	packfile_size = 0;
  	progress = calloc(GOT_FETCH_PKTMAX, 1);
  	if (progress == NULL) {
  		err = got_error_from_errno("calloc");
  		goto done;
  	}
  	while (!done) {
  		struct got_object_id *id = NULL;
  		char *refname = NULL;
  		char *server_progress = NULL;
  		off_t packfile_size_cur = 0;
  
  		err = got_privsep_recv_fetch_progress(&done,
  		    &id, &refname, symrefs, &server_progress,
  		    &packfile_size_cur, &fetchibuf);
  		if (err != NULL)
  			goto done;
  		if (done) {
  			if (packfile_size > 0)
  				*pack_hash = id;
  			else
  				free(id);
  		} else if (refname && id) {
  			err = got_pathlist_insert(NULL, refs, refname, id);
  			if (err)
  				goto done;
  		} else if (server_progress) {
  			char *p;
  			/*
  			 * XXX git-daemon tends to send batched output with
  			 * lines spanning separate packets. Buffer progress
  			 * output until we see a CR or LF to avoid giving
  			 * partial lines of progress output to the callback.
  			 */
  			if (strlcat(progress, server_progress,
  			    GOT_FETCH_PKTMAX) >= GOT_FETCH_PKTMAX) {
  				progress[0] = '\0'; /* discard */
  				continue;
  			}
  			while ((p = strchr(progress, '\r')) != NULL ||
  			    (p = strchr(progress, '\n')) != NULL) {
  				char *s;
  				size_t n;
  				char c = *p;
  				*p = '\0';
  				if (asprintf(&s, "%s%s", progress,
  				    c == '\n' ? "\n" : "") == -1) {
  					err = got_error_from_errno("asprintf");
  					goto done;
  				}
  				err = progress_cb(progress_arg, s,
  				    packfile_size_cur, 0, 0, 0, 0);
  				free(s);
  				if (err)
  					break;
  				n = strlen(progress);
  				if (n < GOT_FETCH_PKTMAX - 1) {
  					memmove(progress, &progress[n + 1],
  					    GOT_FETCH_PKTMAX - n - 1);
  				} else
  					progress[0] = '\0';
  			}
  			free(server_progress);
  			if (err)
  				goto done;
  		} else if (packfile_size_cur != packfile_size) {
  			err = progress_cb(progress_arg, NULL,
  			    packfile_size_cur, 0, 0, 0, 0);
  			if (err)
  				break;
  			packfile_size = packfile_size_cur;
  		}
  	}
  	if (waitpid(fetchpid, &fetchstatus, 0) == -1) {
  		err = got_error_from_errno("waitpid");
  		goto done;
  	}
  
  	if (lseek(packfd, 0, SEEK_SET) == -1) {
  		err = got_error_from_errno("lseek");
  		goto done;
  	}
  
  	/* If zero data was fetched without error we are already up-to-date. */
  	if (packfile_size == 0)
  		goto done;
  	else if (packfile_size < sizeof(pack_hdr) + SHA1_DIGEST_LENGTH) {
  		err = got_error_msg(GOT_ERR_BAD_PACKFILE, "short pack file");
  		goto done;
  	} else {
  		ssize_t n;
  
  		n = read(packfd, &pack_hdr, sizeof(pack_hdr));
  		if (n == -1) {
  			err = got_error_from_errno("read");
  			goto done;
  		}
  		if (n != sizeof(pack_hdr)) {
  			err = got_error(GOT_ERR_IO);
  			goto done;
  		}
  		if (pack_hdr.signature != htobe32(GOT_PACKFILE_SIGNATURE)) {
  			err = got_error_msg(GOT_ERR_BAD_PACKFILE,
  			    "bad pack file signature");
  			goto done;
  		}
  		if (pack_hdr.version != htobe32(GOT_PACKFILE_VERSION)) {
  			err = got_error_msg(GOT_ERR_BAD_PACKFILE,
  			    "bad pack file version");
  			goto done;
  		}
  		nobj = betoh32(pack_hdr.nobjects);
  		if (nobj == 0 &&
  		    packfile_size > sizeof(pack_hdr) + SHA1_DIGEST_LENGTH)
  			return got_error_msg(GOT_ERR_BAD_PACKFILE,
  			    "bad pack file with zero objects");
  		if (nobj != 0 &&
  		    packfile_size <= sizeof(pack_hdr) + SHA1_DIGEST_LENGTH)
  			return got_error_msg(GOT_ERR_BAD_PACKFILE,
  			    "empty pack file with non-zero object count");
  	}
  
  	/*
  	 * If the pack file contains no objects, we may only need to update
  	 * references in our repository. The caller will take care of that.
  	 */
  	if (nobj == 0)
  		goto done;
  
  	if (lseek(packfd, 0, SEEK_SET) == -1) {
  		err = got_error_from_errno("lseek");
  		goto done;
  	}
  
  	err = check_pack_hash(packfd, packfile_size, (*pack_hash)->sha1);
  	if (err)
  		goto done;
  
  	if (lseek(packfd, 0, SEEK_SET) == -1) {
  		err = got_error_from_errno("lseek");
  		goto done;
  	}
   
  	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_idxfds) == -1) {
  		err = got_error_from_errno("socketpair");
  		goto done;
  	}
  	idxpid = fork();
  	if (idxpid == -1) {
  		err= got_error_from_errno("fork");
  		goto done;
  	} else if (idxpid == 0)
  		got_privsep_exec_child(imsg_idxfds,
  		    GOT_PATH_PROG_INDEX_PACK, tmppackpath);
  	if (close(imsg_idxfds[1]) != 0) {
  		err = got_error_from_errno("close");
  		goto done;
  	}
  	imsg_init(&idxibuf, imsg_idxfds[0]);
  
  	npackfd = dup(packfd);
  	if (npackfd == -1) {
  		err = got_error_from_errno("dup");
  		goto done;
  	}
  	err = got_privsep_send_index_pack_req(&idxibuf, (*pack_hash)->sha1,
  	    npackfd);
  	if (err != NULL)
  		goto done;
  	npackfd = -1;
  	err = got_privsep_send_index_pack_outfd(&idxibuf, nidxfd);
  	if (err != NULL)
  		goto done;
  	nidxfd = -1;
  	for (i = 0; i < nitems(tmpfds); i++) {
  		err = got_privsep_send_tmpfd(&idxibuf, tmpfds[i]);
  		if (err != NULL)
  			goto done;
  		tmpfds[i] = -1;
  	}
  	done = 0;
  	while (!done) {
  		int nobj_total, nobj_indexed, nobj_loose, nobj_resolved;
  
  		err = got_privsep_recv_index_progress(&done, &nobj_total,
  		    &nobj_indexed, &nobj_loose, &nobj_resolved,
  		    &idxibuf);
  		if (err != NULL)
  			goto done;
  		if (nobj_indexed != 0) {
  			err = progress_cb(progress_arg, NULL,
  			    packfile_size, nobj_total,
  			    nobj_indexed, nobj_loose, nobj_resolved);
  			if (err)
  				break;
  		}
  		imsg_clear(&idxibuf);
  	}
  	if (close(imsg_idxfds[0]) == -1) {
  		err = got_error_from_errno("close");
  		goto done;
  	}
  	if (waitpid(idxpid, &idxstatus, 0) == -1) {
  		err = got_error_from_errno("waitpid");
  		goto done;
  	}
  
  	err = got_object_id_str(&id_str, *pack_hash);
  	if (err)
  		goto done;
  	if (asprintf(&packpath, "%s/%s/pack-%s.pack",
  	    repo_path, GOT_OBJECTS_PACK_DIR, id_str) == -1) {
  		err = got_error_from_errno("asprintf");
  		goto done;
  	}
  
  	if (asprintf(&idxpath, "%s/%s/pack-%s.idx",
  	    repo_path, GOT_OBJECTS_PACK_DIR, id_str) == -1) {
  		err = got_error_from_errno("asprintf");
  		goto done;
  	}
  
  	if (rename(tmppackpath, packpath) == -1) {
  		err = got_error_from_errno3("rename", tmppackpath, packpath);
  		goto done;
  	}
  	free(tmppackpath);
  	tmppackpath = NULL;
  	if (rename(tmpidxpath, idxpath) == -1) {
  		err = got_error_from_errno3("rename", tmpidxpath, idxpath);
  		goto done;
  	}
  	free(tmpidxpath);
  	tmpidxpath = NULL;
  
  done:
  	if (tmppackpath && unlink(tmppackpath) == -1 && err == NULL)
  		err = got_error_from_errno2("unlink", tmppackpath);
  	if (tmpidxpath && unlink(tmpidxpath) == -1 && err == NULL)
  		err = got_error_from_errno2("unlink", tmpidxpath);
  	if (nfetchfd != -1 && close(nfetchfd) == -1 && err == NULL)
  		err = got_error_from_errno("close");
  	if (npackfd != -1 && close(npackfd) == -1 && err == NULL)
  		err = got_error_from_errno("close");
  	if (packfd != -1 && close(packfd) == -1 && err == NULL)
  		err = got_error_from_errno("close");
  	if (idxfd != -1 && close(idxfd) == -1 && err == NULL)
  		err = got_error_from_errno("close");
  	for (i = 0; i < nitems(tmpfds); i++) {
  		if (tmpfds[i] != -1 && close(tmpfds[i]) == -1 && err == NULL)
  			err = got_error_from_errno("close");
  	}
  	free(tmppackpath);
  	free(tmpidxpath);
  	free(idxpath);
  	free(packpath);
  	free(ref_prefix);
  	free(progress);
  
  	TAILQ_FOREACH(pe, &have_refs, entry) {
  		free((char *)pe->path);
  		free(pe->data);
  	}
  	got_pathlist_free(&have_refs);
  	got_ref_list_free(&my_refs);
  	if (err) {
  		free(*pack_hash);
  		*pack_hash = NULL;
  		TAILQ_FOREACH(pe, refs, entry) {
  			free((void *)pe->path);
  			free(pe->data);
  		}
  		got_pathlist_free(refs);
  		TAILQ_FOREACH(pe, symrefs, entry) {
  			free((void *)pe->path);
  			free(pe->data);
  		}
  		got_pathlist_free(symrefs);
  	}
  	return err;
  }
  

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