vcs.c revision 3f54fd611f536639ec30dd53c48e5ec1897cc7d9
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1989-2012 AT&T Intellectual Property *
* and is licensed under the *
* Eclipse Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.eclipse.org/org/documents/epl-v10.html *
* (with md5 checksum b35adb5213ca9657e911e9befb180842) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* Glenn Fowler <gsf@research.att.com> *
* David Korn <dgk@research.att.com> *
* Eduardo Krell <ekrell@adexus.cl> *
* *
***********************************************************************/
#pragma prototyped
/*
* Herman Rao
* AT&T Research
* 3d version control system interface
*/
#include "3d.h"
#if VCS
#define MAXVID 256
#define MAGIC_STRING "\026\003\023\006"
#define MAGIC_LEN 4
#define DELTA (1 << 0)
#define COMPRESS (1 << 1)
#define CPIO (1 << 2)
typedef struct /* unique id for a sfile in WAN */
{
unsigned long host;
dev_t dev;
ino_t ino;
} Rno_t;
/*
* structure of sfile
*
* attr tags_region delta_region log_region
* __________________________________________________________
* | |T|T|T|T| ......|D |D |..... |T|D |T|D |
* ----------------------------------------------------------
*
*/
typedef struct
{
char magic[4];
int type; /* type of file, i.e., DELTA */
int version; /* RSCS version number */
Rno_t rno; /* rnode */
int tag_reg; /* tags region */
int del_reg; /* delta region */
int log_reg; /* log region */
int basetag; /* base tag */
int base; /* base delta */
int basesize; /* base delta size */
} Attr_t;
#define LOG (1<<0)
#define HASH (1<<1)
#define VCSLINK (1<<2)
#define VOBJ (1<<3)
#define BASE (1<<4)
#define MARKER (1<<5)
typedef struct
{
int length; /* length of tag */
int type; /* type of data */
int del; /* addr of data */
int dsize; /* size of data */
struct stat stat; /* stat info */
int domain; /* domain of the creator */
char version[MAXVID]; /* version id */
} Tag_t;
#define ISBASE(tp) (((tp)->type) & BASE)
#define ISROOT(me) (me == (uid_t)(0))
#define R_ISLINK(tp) (((tp)->type) & VCSLINK)
#define R_ISMARKER(tp) (((tp)->type) & MARKER)
#define CHRLINK '>'
#define CHRMARKER '<'
#define MAXLINKS 10
/*
* used by lookup_tag()
*/
#define L_LOG (1<<0)
#define L_HASH (1<<1)
#define G_LINK (1<<2)
typedef struct Rdirent
{
Tag_t* tag;
int oldaddr; /* for reconf used */
char* link; /* used by the link */
struct Rdirent* next;
} Rdirent_t;
#define ISRSCS(ap) (!strncmp(ap->magic, MAGIC_STRING, MAGIC_LEN))
#define KEYEQ(t,v,r) (streq(t->version, v) && (!r || t->domain == r))
/*
* list of error codes
*/
#define ERRARG 1
#define NOVFILE 2
#define NOTRSCS 3
#define NOVERSION 4
#define NOBASE 5
#define ERRSTRUCT 6
#define ERRBASE 7
#define ERRDELTA 8
#define NOMEM 9
#define ERRUPDATE 10
#define ERRACCESS 11
#define ERRWRITE 12
#define NOENTIES 13
#define DEFAULT "default"
#define LATEST "latest"
#define VCS_RDIR "VCS"
#define VCS_MDIR "..."
#define VCS_MDIRLEN (sizeof(VCS_MDIR)-1)
int
vcs_checkout(const char* path, struct stat* st)
{
char* b;
char* e;
int fd;
int n;
char buf[3 * PATH_MAX];
int synfd;
char synpath[PATH_MAX];
NoP(st);
message((-2, "vcs: checkout: %s", path));
if ((fd = fsfd(state.vcs.fs)) < 0)
{
message((-2, "vcs: connect error"));
return(-1);
}
e = (b = buf) + elementsof(buf) - 1;
bprintf(&b, e, "out %s %s %s\n", state.path.vcs.rfile, state.path.vcs.version, state.path.vcs.rfile);
n = b - buf;
message((-2, "vsc: sendout msg %s", buf));
cancel(&state.vcs.fd);
if (WRITE(fd, buf, n) != n)
{
message((-2, "vcs: checkout: can't send the message %s", buf));
return(-1);
}
e = (b = synpath) + elementsof(synpath) - 1;
bprintf(&b, e, "%s__%d", state.path.vcs.rfile, state.pid);
if ((synfd = OPEN(synpath, O_CREAT | O_WRONLY, 0666)) < 0)
return(-1);
CLOSE(synfd);
if ((n = READ(fd, buf, sizeof(buf) - 1)) > 0)
{
buf[n - 1] = 0;
message((-2, "vcs: checkout return msg %s", buf));
UNLINK(synpath);
return(0);
}
return(-1);
}
/*
* path: prefix/.../file_name/version_name
* rfile: prefix/.../file_name/default
* version: version_name
*/
static int
vcs_map(const char* path, char* rfile, char* version)
{
register const char* s;
const char* p[3];
int i;
for (s = path; *s; s++);
for (i = 0; s != path && i < 3; s--)
if (*s == '/')
p[i++] = s + 1;
s++;
if (i < 3 || s == path || !strneq(p[2], VCS_MDIR, VCS_MDIRLEN))
return(-1);
strcpy(version, p[0]);
strcpy(rfile, path);
message((-2, "vcs: map path=%s rfile=%s version=%s", path, rfile, version));
return(0);
}
static Rdirent_t*
add_entry(Rdirent_t* head, Tag_t* tp)
{
register Rdirent_t* ndp;
register Rdirent_t* dp;
register Rdirent_t** prev_posn;
int result;
Tag_t* ntp;
char* link = 0;
int marker;
if (R_ISLINK(tp) && (link = strrchr(tp->version, CHRLINK)))
*link++ = 0;
marker = R_ISMARKER(tp) ? 1 : 0;
dp = head;
prev_posn = &head;
while (dp)
{
/*
* no marker as this point
*/
#if 0
if (!marker && R_ISMARKER(dp->tag))
{
if ((dp->tag->stat.st_ctime < tp->stat.st_ctime) && markermatch(dp->tag->version, tp->version))
{
*prev_posn = dp->next;
ndp = dp->next;
free(dp->tag);
free(dp);
dp = ndp;
continue;
}
}
#endif
if ((result = strcmp(dp->tag->version, tp->version)) == 0)
{
/*
* check if the minor key (domain) is the same
*/
if (dp->tag->domain == tp->domain)
{
if (dp->tag->stat.st_ctime > tp->stat.st_ctime)
return(head);
ntp = newof(0, Tag_t, 0, tp->length);
memcpy((char*)ntp, (char*)tp, tp->length);
free(dp->tag);
dp->tag = ntp;
if (R_ISLINK(tp) && link)
dp->link = strdup(link);
return(head);
}
}
else if (result > 0)
{
ndp = newof(0, Rdirent_t, 1, 0);
ntp = newof(0, Tag_t, 0, tp->length);
memcpy((char*)ntp, (char*)tp, tp->length);
ndp->tag = ntp;
ndp->next = dp;
if (R_ISLINK(tp) && link)
ndp->link = strdup(link);
*prev_posn = ndp;
return(head);
}
prev_posn = &(dp->next);
dp = dp->next;
}
ndp = newof(0, Rdirent_t, 1, 0);
ntp = newof(0, Tag_t, 0, tp->length);
memcpy((char*)ntp, (char*)tp, tp->length);
ndp->tag = ntp;
ndp->next = 0;
if (R_ISLINK(tp) && link)
ndp->link = strdup(link);
*prev_posn = ndp;
return(head);
}
static Tag_t*
get_tag(int f, register Tag_t* tp)
{
register char* s;
int len;
s = (char *)tp + sizeof(int);
memset((char *)tp, 0, sizeof(Tag_t));
if (!READ(f, (char *)&(tp->length), sizeof(int)) || (len = tp->length - sizeof(int)) && READ(f, (char *)s, len) != len)
return(0);
if (tp->type & LOG)
{
tp->del = lseek(f, 0, SEEK_CUR);
lseek(f, tp->dsize, SEEK_CUR);
}
return(tp);
}
static Rdirent_t*
rs_dir(register int fd, register Attr_t* ap)
{
Tag_t tag;
register Tag_t* tp;
Rdirent_t* head;
register Rdirent_t* dp;
register Rdirent_t* ndp;
register Rdirent_t** prev_posn;
state.vcs.now = time(NiL);
tp = &tag;
head = 0;
lseek(fd, ap->log_reg, SEEK_SET);
while(get_tag(fd, tp))
head = add_entry(head, tp);
lseek(fd, ap->tag_reg, SEEK_SET);
while((lseek(fd, 0, SEEK_CUR)<ap->del_reg) && get_tag(fd, tp))
head = add_entry(head, tp);
/*
* remove expired marker
*/
dp = head;
prev_posn = &head;
while (dp)
{
if (R_ISMARKER(dp->tag) && dp->tag->stat.st_mtime < state.vcs.now)
{
*prev_posn = dp->next;
ndp = dp->next;
free(dp->tag);
free(dp);
dp = ndp;
}
else
{
prev_posn = &(dp->next);
dp = dp->next;
}
}
return(head);
}
static Tag_t*
locate(register Rdirent_t* rdir, register char* version, int level)
{
register Rdirent_t* rd;
register time_t mtime;
register Rdirent_t* p;
if (level > MAXLINKS)
return(0);
if (streq(version, DEFAULT) || streq(version, LATEST))
{
for (rd = rdir, mtime = 0L; rd; rd = rd->next)
{
if (rd->tag->stat.st_mtime > mtime)
{
p = rd;
mtime = rd->tag->stat.st_mtime;
}
}
if (mtime)
return(p->tag);
}
rd = rdir;
for (rd = rdir; rd; rd = rd->next)
{
if (streq(rd->tag->version, version))
{
if (R_ISLINK(rd->tag))
return(locate(rdir, rd->link, level +1));
return(rd->tag);
}
}
return(0);
}
static void
free_dir(register Rdirent_t* rdir)
{
Rdirent_t* rnext;
while(rdir)
{
rnext = rdir->next;
free(rdir->tag);
if (rdir->link)
free(rdir->link);
free(rdir);
rdir = rnext;
}
return;
}
/*
* return 0 if found it;
* -1 if error
* 1 if not found.
*/
static int
vcs_stat(int fd, char* version, struct stat* st, off_t size)
{
static Attr_t* ap = 0;
static Attr_t apbuf;
static Rdirent_t* rdir = 0;
register Tag_t* tag;
NoP(size);
if (fd != state.vcs.fd || !ap)
{
ap = &apbuf;
if (READ(fd, (char *)ap, sizeof(Attr_t)) != sizeof(Attr_t))
return(-1);
if (!rdir)
free_dir(rdir);
if (!(rdir = rs_dir(fd, ap)))
return(1);
}
if (tag = locate(rdir, version, 0))
{
*st = tag->stat;
return(0);
}
return(1);
}
int
vcs_real(const char* path, struct stat* st)
{
int n;
int fd;
message((-2, "vcs: path=%s", path));
if (st->st_nlink <= 1 || vcs_map(path, state.path.vcs.rfile, state.path.vcs.version))
return(-1);
message((-2, "vcs: real path=%s rfile=%s version=%s", path, state.path.vcs.rfile, state.path.vcs.version));
if (state.vcs.fd && state.vcs.dev == st->st_dev && state.vcs.ino == st->st_ino)
fd = state.vcs.fd;
else if ((fd = OPEN(path, O_RDONLY, 0)) < 0)
return(-1);
if (n = vcs_stat(fd, state.path.vcs.version, st, st->st_size))
{
if (fd != state.vcs.fd) CLOSE(fd);
else if (n == -1) cancel(&state.vcs.fd);
return(-1);
}
if (fd != state.vcs.fd)
{
cancel(&state.vcs.fd);
state.vcs.fd = fd;
reserve(&state.vcs.fd);
state.vcs.dev = st->st_dev;
state.vcs.ino = st->st_ino;
FCNTL(fd, F_SETFD, FD_CLOEXEC);
}
return(0);
}
int
vcs_set(Fs_t* fs, const char* arg, int argsize, const char* op, int opsize)
{
NoP(arg);
NoP(argsize);
NoP(op);
NoP(opsize);
state.vcs.fs = fs;
return(0);
}
#else
NoN(vcs)
#endif