ref: d916a4c3823f55227ffae35738c2497256e307b5
dir: /appl/cmd/ar.b/
implement Ar;
#
# ar - portable (ascii) format version
#
include "sys.m";
sys: Sys;
include "draw.m";
include "bufio.m";
bufio: Bufio;
Iobuf: import bufio;
include "daytime.m";
daytime: Daytime;
include "string.m";
str: String;
Ar: module
{
init: fn(nil: ref Draw->Context, nil: list of string);
};
ARMAG: con "!<arch>\n";
SARMAG: con len ARMAG;
ARFMAG0: con byte '`';
ARFMAG1: con byte '\n';
SARNAME: con 16; # ancient limit
#
# printable archive header
# name[SARNAME] date[12] uid[6] gid[6] mode[8] size[10] fmag[2]
#
Oname: con 0;
Lname: con SARNAME;
Odate: con Oname+Lname;
Ldate: con 12;
Ouid: con Odate+Ldate;
Luid: con 6;
Ogid: con Ouid+Luid;
Lgid: con 6;
Omode: con Ogid+Lgid;
Lmode: con 8;
Osize: con Omode+Lmode;
Lsize: con 10;
Ofmag: con Osize+Lsize;
Lfmag: con 2;
SAR_HDR: con Ofmag+Lfmag; # 60
#
# The algorithm uses up to 3 temp files. The "pivot contents" is the
# archive contents specified by an a, b, or i option. The temp files are
# astart - contains existing contentss up to and including the pivot contents.
# amiddle - contains new files moved or inserted behind the pivot.
# aend - contains the existing contentss that follow the pivot contents.
# When all contentss have been processed, function 'install' streams the
# temp files, in order, back into the archive.
#
Armember: adt { # one per archive contents
name: string; # trimmed
length: int;
date: int;
uid: int;
gid: int;
mode: int;
size: int;
contents: array of byte;
fd: ref Sys->FD; # if contents is nil and fd is not nil, fd has contents
next: cyclic ref Armember;
new: fn(name: string, fd: ref Sys->FD): ref Armember;
rdhdr: fn(b: ref Iobuf): ref Armember;
read: fn(m: self ref Armember, b: ref Iobuf): int;
wrhdr: fn(m: self ref Armember, fd: ref Sys->FD);
write: fn(m: self ref Armember, fd: ref Sys->FD);
skip: fn(m: self ref Armember, b: ref Iobuf);
replace: fn(m: self ref Armember, name: string, fd: ref Sys->FD);
copyout: fn(m: self ref Armember, b: ref Iobuf, destfd: ref Sys->FD);
};
Arfile: adt { # one per tempfile
fd: ref Sys->FD; # paging file descriptor, nil if none allocated
head: ref Armember;
tail: ref Armember;
new: fn(): ref Arfile;
copy: fn(ar: self ref Arfile, b: ref Iobuf, mem: ref Armember);
insert: fn(ar: self ref Arfile, mem: ref Armember);
stream: fn(ar: self ref Arfile, fd: ref Sys->FD);
page: fn(ar: self ref Arfile): int;
};
File: adt {
name: string;
trimmed: string;
found: int;
};
man := "mrxtdpq";
opt := "uvnbailo";
aflag := 0;
bflag := 0;
cflag := 0;
oflag := 0;
uflag := 0;
vflag := 0;
pivotname: string;
bout: ref Iobuf;
stderr: ref Sys->FD;
parts: array of ref Arfile;
comfun: ref fn(a: string, f: array of ref File);
init(nil: ref Draw->Context, args: list of string)
{
sys = load Sys Sys->PATH;
bufio = load Bufio Bufio->PATH;
daytime = load Daytime Daytime->PATH;
str = load String String->PATH;
stderr = sys->fildes(2);
bout = bufio->fopen(sys->fildes(1), Sys->OWRITE);
if(len args < 3)
usage();
args = tl args;
s := hd args; args = tl args;
for(i := 0; i < len s; i++){
case s[i] {
'a' => aflag = 1;
'b' => bflag = 1;
'c' => cflag = 1;
'd' => setcom(dcmd);
'i' => bflag = 1;
'l' => ; # ignored
'm' => setcom(mcmd);
'o' => oflag = 1;
'p' => setcom(pcmd);
'q' => setcom(qcmd);
'r' => setcom(rcmd);
't' => setcom(tcmd);
'u' => uflag = 1;
'v' => vflag = 1;
'x' => setcom(xcmd);
* =>
sys->fprint(stderr, "ar: bad option `%c'\n", s[i]);
usage();
}
}
if(aflag && bflag){
sys->fprint(stderr, "ar: only one of 'a' and 'b' can be specified\n");
usage();
}
if(aflag || bflag){
pivotname = trim(hd args); args = tl args;
if(len args < 2)
usage();
}
if(comfun == nil){
if(uflag == 0){
sys->fprint(stderr, "ar: one of [%s] must be specified\n", man);
usage();
}
setcom(rcmd);
}
cp := hd args; args = tl args;
files := array[len args] of ref File;
for(i = 0; args != nil; args = tl args)
files[i++] = ref File(hd args, trim(hd args), 0);
comfun(cp, files); # do the command
allfound := 1;
for(i = 0; i < len files; i++)
if(!files[i].found){
sys->fprint(stderr, "ar: %s not found\n", files[i].name);
allfound = 0;
}
bout.flush();
if(!allfound)
raise "fail: file not found";
}
#
# select a command
#
setcom(fun: ref fn(s: string, f: array of ref File))
{
if(comfun != nil){
sys->fprint(stderr, "ar: only one of [%s] allowed\n", man);
usage();
}
comfun = fun;
}
#
# perform the 'r' and 'u' commands
#
rcmd(arname: string, files: array of ref File)
{
bar := openar(arname, Sys->ORDWR, 1);
parts = array[2] of {Arfile.new(), nil};
ap := parts[0];
if(bar != nil){
while((mem := Armember.rdhdr(bar)) != nil){
if(bamatch(mem.name, pivotname)) # check for pivot
ap = parts[1] = Arfile.new();
f := match(files, mem.name);
if(f == nil){
ap.copy(bar, mem);
continue;
}
f.found = 1;
dfd := sys->open(f.name, Sys->OREAD);
if(dfd == nil){
if(len files > 0)
sys->fprint(stderr, "ar: cannot open %s: %r\n", f.name);
ap.copy(bar, mem);
continue;
}
if(uflag){
(ok, d) := sys->fstat(dfd);
if(ok < 0 || d.mtime <= mem.date){
if(ok < 0)
sys->fprint(stderr, "ar: cannot stat %s: %r\n", f.name);
ap.copy(bar, mem);
continue;
}
}
mem.skip(bar);
mesg('r', f.name);
mem.replace(f.name, dfd);
ap.insert(mem);
dfd = nil;
}
}
# copy in remaining files named on command line
for(i := 0; i < len files; i++){
f := files[i];
if(f.found)
continue;
f.found = 1;
dfd := sys->open(f.name, Sys->OREAD);
if(dfd != nil){
mesg('a', f.name);
parts[0].insert(Armember.new(f.trimmed, dfd));
}else
sys->fprint(stderr, "ar: cannot open %s: %r\n", f.name);
}
if(bar == nil && !cflag)
install(arname, parts, 1); # issue 'creating' msg
else
install(arname, parts, 0);
}
dcmd(arname: string, files: array of ref File)
{
if(len files == 0)
return;
changed := 0;
parts = array[] of {Arfile.new()};
bar := openar(arname, Sys->ORDWR, 0);
while((mem := Armember.rdhdr(bar)) != nil){
if(match(files, mem.name) != nil){
mesg('d', mem.name);
mem.skip(bar);
changed = 1;
}else
parts[0].copy(bar, mem);
mem = nil; # conserves memory
}
if(changed)
install(arname, parts, 0);
}
xcmd(arname: string, files: array of ref File)
{
bar := openar(arname, Sys->OREAD, 0);
i := 0;
while((mem := Armember.rdhdr(bar)) != nil){
if((f := match(files, mem.name)) != nil){
f.found = 1;
fd := sys->create(f.name, Sys->OWRITE, mem.mode & 8r777);
if(fd == nil){
sys->fprint(stderr, "ar: cannot create %s: %r\n", f.name);
mem.skip(bar);
}else{
mesg('x', f.name);
mem.copyout(bar, fd);
if(oflag){
dx := sys->nulldir;
dx.atime = mem.date;
dx.mtime = mem.date;
if(sys->fwstat(fd, dx) < 0)
sys->fprint(stderr, "ar: can't set times on %s: %r", f.name);
}
fd = nil;
mem = nil;
}
if(len files > 0 && ++i >= len files)
break;
}else
mem.skip(bar);
}
}
pcmd(arname: string, files: array of ref File)
{
bar := openar(arname, Sys->OREAD, 0);
i := 0;
while((mem := Armember.rdhdr(bar)) != nil){
if((f := match(files, mem.name)) != nil){
if(vflag)
sys->print("\n<%s>\n\n", f.name);
mem.copyout(bar, sys->fildes(1));
if(len files > 0 && ++i >= len files)
break;
}else
mem.skip(bar);
mem = nil; # we no longer need the contents
}
}
mcmd(arname: string, files: array of ref File)
{
if(len files == 0)
return;
parts = array[3] of {Arfile.new(), Arfile.new(), nil};
bar := openar(arname, Sys->ORDWR, 0);
ap := parts[0];
while((mem := Armember.rdhdr(bar)) != nil){
if(bamatch(mem.name, pivotname))
ap = parts[2] = Arfile.new();
if((f := match(files, mem.name)) != nil){
mesg('m', f.name);
parts[1].copy(bar, mem);
}else
ap.copy(bar, mem);
}
if(pivotname != nil && parts[2] == nil)
sys->fprint(stderr, "ar: %s not found - files moved to end\n", pivotname);
install(arname, parts, 0);
}
tcmd(arname: string, files: array of ref File)
{
bar := openar(arname, Sys->OREAD, 0);
while((mem := Armember.rdhdr(bar)) != nil){
if((f := match(files, mem.name)) != nil){
longls := "";
if(vflag)
longls = longtext(mem)+" ";
bout.puts(longls+f.trimmed+"\n");
}
mem.skip(bar);
mem = nil;
}
}
qcmd(arname: string, files: array of ref File)
{
if(aflag || bflag){
sys->fprint(stderr, "ar: abi not allowed with q\n");
raise "fail:usage";
}
fd := openrawar(arname, Sys->ORDWR, 1);
if(fd == nil){
if(!cflag)
sys->fprint(stderr, "ar: creating %s\n", arname);
fd = arcreate(arname);
}
# leave note group behind when writing archive; i.e. sidestep interrupts
sys->seek(fd, big 0, 2); # append
for(i := 0; i < len files; i++){
f := files[i];
f.found = 1;
dfd := sys->open(f.name, Sys->OREAD);
if(dfd != nil){
mesg('q', f.name);
mem := Armember.new(f.trimmed, dfd);
if(mem != nil){
mem.write(fd);
mem = nil;
}
}else
sys->fprint(stderr, "ar: cannot open %s: %r\n", f.name);
}
}
#
# open an archive and validate its header
#
openrawar(arname: string, mode: int, errok: int): ref Sys->FD
{
fd := sys->open(arname, mode);
if(fd == nil){
if(!errok){
sys->fprint(stderr, "ar: cannot open %s: %r\n", arname);
raise "fail:error";
}
return nil;
}
mbuf := array[SARMAG] of byte;
if(sys->read(fd, mbuf, SARMAG) != SARMAG || string mbuf != ARMAG){
sys->fprint(stderr, "ar: %s not in archive format\n", arname);
raise "fail:error";
}
return fd;
}
openar(arname: string, mode: int, errok: int): ref Iobuf
{
fd := openrawar(arname, mode, errok);
if(fd == nil)
return nil;
bfd := bufio->fopen(fd, mode);
bfd.seek(big SARMAG, 0);
return bfd;
}
#
# create an archive and set its header
#
arcreate(arname: string): ref Sys->FD
{
fd := sys->create(arname, Sys->OWRITE, 8r666);
if(fd == nil){
sys->fprint(stderr, "ar: cannot create %s: %r\n", arname);
raise "fail:create";
}
a := array of byte ARMAG;
mustwrite(fd, a, len a);
return fd;
}
#
# error handling
#
wrerr()
{
sys->fprint(stderr, "ar: write error: %r\n");
raise "fail:write error";
}
rderr()
{
sys->fprint(stderr, "ar: read error: %r\n");
raise "fail:read error";
}
phaseerr(offset: big)
{
sys->fprint(stderr, "ar: phase error at offset %bd\n", offset);
raise "fail:phase error";
}
usage()
{
sys->fprint(stderr, "usage: ar [%s][%s] archive files ...\n", opt, man);
raise "fail:usage";
}
#
# concatenate the several sequences of members into one archive
#
install(arname: string, seqs: array of ref Arfile, createflag: int)
{
# leave process group behind when copying back; i.e. sidestep interrupts
sys->pctl(Sys->NEWPGRP, nil);
if(createflag)
sys->fprint(stderr, "ar: creating %s\n", arname);
fd := arcreate(arname);
for(i := 0; i < len seqs; i++)
if((ap := seqs[i]) != nil)
ap.stream(fd);
}
#
# return the command line File matching a given name
#
match(files: array of ref File, file: string): ref File
{
if(len files == 0)
return ref File(file, file, 0); # empty list always matches
for(i := 0; i < len files; i++)
if(!files[i].found && files[i].trimmed == file){
files[i].found = 1;
return files[i];
}
return nil;
}
#
# is `file' the pivot member's name and is the archive positioned
# at the correct point wrt after or before options? return true if so.
#
state := 0;
bamatch(file: string, pivot: string): int
{
case state {
0 => # looking for position file
if(aflag){
if(file == pivot)
state = 1;
}else if(bflag){
if(file == pivot){
state = 2; # found
return 1;
}
}
1 => # found - after previous file
state = 2;
return 1;
2 => # already found position file
;
}
return 0;
}
#
# output a message, if 'v' option was specified
#
mesg(c: int, file: string)
{
if(vflag)
bout.puts(sys->sprint("%c - %s\n", c, file));
}
#
# return just the file name
#
trim(s: string): string
{
for(j := len s; j > 0 && s[j-1] == '/';)
j--;
k := 0;
for(i := 0; i < j; i++)
if(s[i] == '/')
k = i+1;
return s[k: j];
}
longtext(mem: ref Armember): string
{
s := modes(mem.mode);
s += sys->sprint(" %3d/%1d", mem.uid, mem.gid);
s += sys->sprint(" %7ud", mem.size);
t := daytime->text(daytime->local(mem.date));
return s+sys->sprint(" %-12.12s %-4.4s ", t[4:], t[24:]);
}
mtab := array[] of {
"---", "--x", "-w-", "-wx",
"r--", "r-x", "rw-", "rwx"
};
modes(mode: int): string
{
return mtab[(mode>>6)&7]+mtab[(mode>>3)&7]+mtab[mode&7];
}
#
# read the header for the next archive contents
#
Armember.rdhdr(b: ref Iobuf): ref Armember
{
buf := array[SAR_HDR] of byte;
if((n := b.read(buf, len buf)) != len buf){
if(n == 0)
return nil;
if(n > 0)
sys->werrstr("unexpected end-of-file");
rderr();
}
mem := ref Armember;
for(i := Oname+Lname; i > Oname; i--)
if(buf[i-1] != byte '/' && buf[i-1] != byte ' ')
break;
mem.name = string buf[Oname:i];
mem.date = intof(buf[Odate: Odate+Ldate], 10);
mem.uid = intof(buf[Ouid: Ouid+Luid], 10);
mem.gid = intof(buf[Ogid: Ogid+Lgid], 10);
mem.mode = intof(buf[Omode: Omode+Lmode], 8);
mem.size = intof(buf[Osize: Osize+Lsize], 10);
if(buf[Ofmag] != ARFMAG0 || buf[Ofmag+1] != ARFMAG1)
phaseerr(b.offset()-big SAR_HDR);
return mem;
}
intof(a: array of byte, base: int): int
{
for(i := len a; i > 0; i--)
if(a[i-1] != byte ' '){
a = a[0:i];
break;
}
(n, s) := str->toint(string a, base);
if(s != nil){
sys->fprint(stderr, "ar: invalid integer in archive member's header: %q\n", string a);
raise "fail:error";
}
return n;
}
Armember.wrhdr(mem: self ref Armember, fd: ref Sys->FD)
{
b := array[SAR_HDR] of {* => byte ' '};
nm := array of byte mem.name;
if(len nm > Lname)
nm = nm[0:Lname];
b[Oname:] = nm;
b[Odate:] = sys->aprint("%-12ud", mem.date);
b[Ouid:] = sys->aprint("%-6d", 0);
b[Ogid:] = sys->aprint("%-6d", 0);
b[Omode:] = sys->aprint("%-8uo", mem.mode);
b[Osize:] = sys->aprint("%-10ud", mem.size);
b[Ofmag] = ARFMAG0;
b[Ofmag+1] = ARFMAG1;
mustwrite(fd, b, len b);
}
#
# make a new member from the given file, with the file's contents
#
Armember.new(name: string, fd: ref Sys->FD): ref Armember
{
mem := ref Armember;
mem.replace(name, fd);
return mem;
}
#
# replace the contents of an existing member
#
Armember.replace(mem: self ref Armember, name: string, fd: ref Sys->FD)
{
(ok, d) := sys->fstat(fd);
if(ok < 0){
sys->fprint(stderr, "ar: cannot stat %s: %r\n", name);
raise "fail:no stat";
}
mem.name = trim(name);
mem.date = d.mtime;
mem.uid = 0;
mem.gid = 0;
mem.mode = d.mode & 8r777;
mem.size = int d.length;
if(big mem.size != d.length){
sys->fprint(stderr, "ar: file %s too big\n", name);
raise "fail:error";
}
mem.fd = fd;
mem.contents = nil; # will be copied across from fd when needed
}
#
# read the contents of an archive member
#
Armember.read(mem: self ref Armember, b: ref Iobuf): int
{
if(mem.contents != nil)
return len mem.contents;
mem.contents = buffer(mem.size + (mem.size&1));
n := b.read(mem.contents, len mem.contents);
if(n != len mem.contents){
if(n >= 0)
sys->werrstr("unexpected end-of-file");
rderr();
}
return n;
}
mustwrite(fd: ref Sys->FD, buf: array of byte, n: int)
{
if(sys->write(fd, buf, n) != n)
wrerr();
}
#
# write an archive member to ofd, including header
#
Armember.write(mem: self ref Armember, ofd: ref Sys->FD)
{
mem.wrhdr(ofd);
if(mem.contents != nil){
mustwrite(ofd, mem.contents, len mem.contents);
return;
}
if(mem.fd == nil)
raise "ar: write nil fd";
buf := array[Sys->ATOMICIO] of byte; # could be bigger
for(nr := mem.size; nr > 0;){
n := nr;
if(n > len buf)
n = len buf;
n = sys->read(mem.fd, buf, n);
if(n <= 0){
if(n == 0)
sys->werrstr("unexpected end-of-file");
rderr();
}
mustwrite(ofd, buf, n);
nr -= n;
}
if(mem.size & 1)
mustwrite(ofd, array[] of {byte '\n'}, 1);
}
#
# seek past the current member's contents in b
#
Armember.skip(mem: self ref Armember, b: ref Iobuf)
{
b.seek(big(mem.size + (mem.size&1)), 1);
}
#
# copy a member's contents from memory or directly from an archive to another file
#
Armember.copyout(mem: self ref Armember, b: ref Iobuf, ofd: ref Sys->FD)
{
if(mem.contents != nil){
mustwrite(ofd, mem.contents, len mem.contents);
return;
}
buf := array[Sys->ATOMICIO] of byte; # could be bigger
for(nr := mem.size; nr > 0;){
n := nr;
if(n > len buf)
n = len buf;
n = b.read(buf, n);
if(n <= 0){
if(n == 0)
sys->werrstr("unexpected end-of-file");
rderr();
}
mustwrite(ofd, buf, n);
nr -= n;
}
if(mem.size & 1)
b.getc();
}
#
# Temp file I/O subsystem. We attempt to cache all three temp files in
# core. When we run out of memory we spill to disk.
# The I/O model assumes that temp files:
# 1) are only written on the end
# 2) are only read from the beginning
# 3) are only read after all writing is complete.
# The architecture uses one control block per temp file. Each control
# block anchors a chain of buffers, each containing an archive contents.
#
Arfile.new(): ref Arfile
{
return ref Arfile;
}
#
# copy the contents of mem at b into the temporary
#
Arfile.copy(ap: self ref Arfile, b: ref Iobuf, mem: ref Armember)
{
mem.read(b);
ap.insert(mem);
}
#
# insert a contents buffer into the contents chain
#
Arfile.insert(ap: self ref Arfile, mem: ref Armember)
{
mem.next = nil;
if(ap.head == nil)
ap.head = mem;
else
ap.tail.next = mem;
ap.tail = mem;
}
#
# stream the contents in a temp file to the file referenced by 'fd'.
#
Arfile.stream(ap: self ref Arfile, fd: ref Sys->FD)
{
if(ap.fd != nil){ # copy prefix from disk
buf := array[Sys->ATOMICIO] of byte;
sys->seek(ap.fd, big 0, 0);
while((n := sys->read(ap.fd, buf, len buf)) > 0)
mustwrite(fd, buf, n);
if(n < 0)
rderr();
ap.fd = nil;
}
# dump the in-core buffers, which always follow the contents in the temp file
for(mem := ap.head; mem != nil; mem = mem.next)
mem.write(fd);
}
#
# spill a member's contents to disk
#
totalmem := 0;
warned := 0;
tn := 0;
Arfile.page(ap: self ref Arfile): int
{
mem := ap.head;
if(ap.fd == nil && !warned){
pid := sys->pctl(0, nil);
for(i := 0;; i++){
name := sys->sprint("/tmp/art%d.%d.%d", pid, tn, i);
ap.fd = sys->create(name, Sys->OEXCL | Sys->ORDWR | Sys->ORCLOSE, 8r600);
if(ap.fd != nil)
break;
if(i >= 20){
warned =1;
sys->fprint(stderr,"ar: warning: can't create temp file %s: %r\n", name);
return 0; # we'll simply use the memory
}
}
tn++;
}
mem.write(ap.fd);
ap.head = mem.next;
if(ap.tail == mem)
ap.tail = mem.next;
totalmem -= len mem.contents;
return 1;
}
#
# account for the space taken by a contents's contents,
# pushing earlier contentss to disk to keep the space below a
# reasonable level
#
buffer(n: int): array of byte
{
Flush:
while(totalmem + n > 1024*1024){
for(i := 0; i < len parts; i++)
if(parts[i] != nil && parts[i].page())
continue Flush;
break;
}
totalmem += n;
return array[n] of byte;
}