ref: 768963687f66b324a6442ec46e1d9939944ed37a
dir: /fetch.c/
#include <u.h> #include <libc.h> #include "git.h" char *fetchbranch; char *upstream = "origin"; char *packtmp = ".git/objects/pack/fetch.tmp"; int listonly; int resolveremote(Hash *h, char *ref) { char buf[128], *s; int r, f; ref = strip(ref); if((r = hparse(h, ref)) != -1) return r; /* Slightly special handling: translate remote refs to local ones. */ if(strcmp(ref, "HEAD") == 0){ snprint(buf, sizeof(buf), ".git/HEAD"); }else if(strstr(ref, "refs/heads") == ref){ ref += strlen("refs/heads"); snprint(buf, sizeof(buf), ".git/refs/remotes/%s/%s", upstream, ref); }else if(strstr(ref, "refs/tags") == ref){ ref += strlen("refs/tags"); snprint(buf, sizeof(buf), ".git/refs/tags/%s/%s", upstream, ref); }else{ return -1; } r = -1; s = strip(buf); if((f = open(s, OREAD)) == -1) return -1; if(readn(f, buf, sizeof(buf)) >= 40) r = hparse(h, buf); close(f); if(r == -1 && strstr(buf, "ref:") == buf) return resolveremote(h, buf + strlen("ref:")); return r; } int rename(char *pack, char *idx, Hash h) { char name[128]; Dir st; nulldir(&st); st.name = name; snprint(name, sizeof(name), "%H.pack", h); if(access(name, AEXIST) == 0) fprint(2, "warning, pack %s already fetched\n", name); else if(dirwstat(pack, &st) == -1) return -1; snprint(name, sizeof(name), "%H.idx", h); if(access(name, AEXIST) == 0) fprint(2, "warning, pack %s already indexed\n", name); else if(dirwstat(idx, &st) == -1) return -1; return 0; } int checkhash(int fd, vlong sz, Hash *hcomp) { DigestState *st; Hash hexpect; char buf[Pktmax]; vlong n, r; int nr; if(sz < 28){ werrstr("undersize packfile"); return -1; } st = nil; n = 0; while(n != sz - 20){ nr = sizeof(buf); if(sz - n - 20 < sizeof(buf)) nr = sz - n - 20; r = readn(fd, buf, nr); if(r != nr) return -1; st = sha1((uchar*)buf, nr, nil, st); n += r; } sha1(nil, 0, hcomp->h, st); if(readn(fd, hexpect.h, sizeof(hexpect.h)) != sizeof(hexpect.h)) sysfatal("truncated packfile"); if(!hasheq(hcomp, &hexpect)){ werrstr("bad hash: %H != %H", *hcomp, hexpect); return -1; } return 0; } int mkoutpath(char *path) { char s[128]; char *p; int fd; snprint(s, sizeof(s), "%s", path); for(p=strchr(s+1, '/'); p; p=strchr(p+1, '/')){ *p = 0; if(access(s, AEXIST) != 0){ fd = create(s, OREAD, DMDIR | 0755); if(fd == -1) return -1; close(fd); } *p = '/'; } return 0; } int branchmatch(char *br, char *pat) { char name[128]; if(strstr(pat, "refs/heads") == pat) snprint(name, sizeof(name), "%s", pat); else if(strstr(pat, "heads")) snprint(name, sizeof(name), "refs/%s", pat); else snprint(name, sizeof(name), "refs/heads/%s", pat); return strcmp(br, name) == 0; } char * matchcap(char *s, char *cap, int full) { if(strncmp(s, cap, strlen(cap)) == 0) if(!full || strlen(s) == strlen(cap)) return s + strlen(cap); return nil; } void handlecaps(char *caps) { char *p, *n, *c, *r; for(p = caps; p != nil; p = n){ n = strchr(p, ' '); if(n != nil) *n++ = 0; if((c = matchcap(p, "symref=", 0)) != nil){ if((r = strchr(c, ':')) != nil){ *r++ = '\0'; print("symref %s %s\n", c, r); } } } } int fetchpack(Conn *c, int pfd, char *packtmp) { char buf[Pktmax], idxtmp[256], *sp[3]; Hash h, *have, *want; int nref, refsz, first; int i, n, req; vlong packsz; Object *o; nref = 0; refsz = 16; first = 1; have = emalloc(refsz * sizeof(have[0])); want = emalloc(refsz * sizeof(want[0])); while(1){ n = readpkt(c, buf, sizeof(buf)); if(n == -1) return -1; if(n == 0) break; if(strncmp(buf, "ERR ", 4) == 0) sysfatal("%s", buf + 4); if(first && n > strlen(buf)) handlecaps(buf + strlen(buf) + 1); first = 0; getfields(buf, sp, nelem(sp), 1, " \t\n\r"); if(strstr(sp[1], "^{}")) continue; if(fetchbranch && !branchmatch(sp[1], fetchbranch)) continue; if(refsz == nref + 1){ refsz *= 2; have = erealloc(have, refsz * sizeof(have[0])); want = erealloc(want, refsz * sizeof(want[0])); } if(hparse(&want[nref], sp[0]) == -1) sysfatal("invalid hash %s", sp[0]); if (resolveremote(&have[nref], sp[1]) == -1) memset(&have[nref], 0, sizeof(have[nref])); print("remote %s %H local %H\n", sp[1], want[nref], have[nref]); nref++; } if(listonly){ flushpkt(c); return 0; } if(writephase(c) == -1) sysfatal("write: %r"); req = 0; for(i = 0; i < nref; i++){ if(hasheq(&have[i], &want[i])) continue; if((o = readobject(want[i])) != nil){ unref(o); continue; } n = snprint(buf, sizeof(buf), "want %H\n", want[i]); if(writepkt(c, buf, n) == -1) sysfatal("could not send want for %H", want[i]); req = 1; } flushpkt(c); for(i = 0; i < nref; i++){ if(hasheq(&have[i], &Zhash)) continue; n = snprint(buf, sizeof(buf), "have %H\n", have[i]); if(writepkt(c, buf, n + 1) == -1) sysfatal("could not send have for %H", have[i]); } if(!req) flushpkt(c); n = snprint(buf, sizeof(buf), "done\n"); if(writepkt(c, buf, n) == -1) sysfatal("write: %r"); if(!req) return 0; if(readphase(c) == -1) sysfatal("read: %r"); if((n = readpkt(c, buf, sizeof(buf))) == -1) sysfatal("read: %r"); buf[n] = 0; fprint(2, "fetching...\n"); packsz = 0; while(1){ n = readn(c->rfd, buf, sizeof buf); if(n == 0) break; if(n == -1 || write(pfd, buf, n) != n) sysfatal("fetch packfile: %r"); packsz += n; } closeconn(c); if(seek(pfd, 0, 0) == -1) sysfatal("packfile seek: %r"); if(checkhash(pfd, packsz, &h) == -1) sysfatal("corrupt packfile: %r"); close(pfd); n = strlen(packtmp) - strlen(".tmp"); memcpy(idxtmp, packtmp, n); memcpy(idxtmp + n, ".idx", strlen(".idx") + 1); if(indexpack(packtmp, idxtmp, h) == -1) sysfatal("could not index fetched pack: %r"); if(rename(packtmp, idxtmp, h) == -1) sysfatal("could not rename indexed pack: %r"); return 0; } void usage(void) { fprint(2, "usage: %s [-b br] remote\n", argv0); fprint(2, "\t-b br: only fetch matching branch 'br'\n"); fprint(2, "remote: fetch from this repository\n"); exits("usage"); } void main(int argc, char **argv) { int pfd; Conn c; ARGBEGIN{ case 'b': fetchbranch=EARGF(usage()); break; case 'u': upstream=EARGF(usage()); break; case 'd': chattygit++; break; case 'l': listonly++; break; default: usage(); break; }ARGEND; gitinit(); if(argc != 1) usage(); if(mkoutpath(packtmp) == -1) sysfatal("could not create %s: %r", packtmp); if((pfd = create(packtmp, ORDWR, 0644)) == -1) sysfatal("could not create %s: %r", packtmp); if(gitconnect(&c, argv[0], "upload") == -1) sysfatal("could not dial %s: %r", argv[0]); if(fetchpack(&c, pfd, packtmp) == -1) sysfatal("fetch failed: %r"); closeconn(&c); exits(nil); }