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authorRob Landley <rob@landley.net>2019-05-19 01:11:05 -0500
committerRob Landley <rob@landley.net>2019-05-19 01:11:05 -0500
commitcfa0256519bd4ef694a7426882160902bab7dece (patch)
tree0b5b07f8367895942ac9533414a41274604c0150 /toys
parentd2df2d5f64de0859c4f91ef44997bce3c3700401 (diff)
downloadtoybox-cfa0256519bd4ef694a7426882160902bab7dece.tar.gz
Add --sparse file creation support to tar.
And fix tar cv to produce output to stderr when archive going to stdout.
Diffstat (limited to 'toys')
-rw-r--r--toys/posix/tar.c79
1 files changed, 64 insertions, 15 deletions
diff --git a/toys/posix/tar.c b/toys/posix/tar.c
index 24f27678..49b1aa1f 100644
--- a/toys/posix/tar.c
+++ b/toys/posix/tar.c
@@ -184,7 +184,7 @@ static int add_to_tar(struct dirtree *node)
struct passwd *pw = pw;
struct group *gr = gr;
int i, fd =-1;
- char *c, *p, *name, *lnk = lnk, *hname;
+ char *name, *lnk, *hname;
if (!dirtree_notdotdot(node)) return 0;
if (TT.adev == st->st_dev && TT.aino == st->st_ino) {
@@ -196,10 +196,10 @@ static int add_to_tar(struct dirtree *node)
name = dirtree_path(node, &i);
// exclusion defaults to --no-anchored and --wildcards-match-slash
- for (p = name; *p;) {
- if (filter(TT.excl, p)) goto done;
- while (*p && *p!='/') p++;
- while (*p=='/') p++;
+ for (lnk = name; *lnk;) {
+ if (filter(TT.excl, lnk)) goto done;
+ while (*lnk && *lnk!='/') lnk++;
+ while (*lnk=='/') lnk++;
}
// Consume the 1 extra byte alocated in dirtree_path()
@@ -207,12 +207,12 @@ static int add_to_tar(struct dirtree *node)
// remove leading / and any .. entries from saved name
for (hname = name; *hname == '/'; hname++);
- for (c = hname;;) {
- if (!(c = strstr(c, ".."))) break;
- if (c == hname || c[-1] == '/') {
- if (!c[2]) goto done;
- if (c[2]=='/') c = hname = c+3;
- } else c+= 2;
+ for (lnk = hname;;) {
+ if (!(lnk = strstr(lnk, ".."))) break;
+ if (lnk == hname || lnk[-1] == '/') {
+ if (!lnk[2]) goto done;
+ if (lnk[2]=='/') lnk = hname = lnk+3;
+ } else lnk+= 2;
}
if (!*hname) goto done;
@@ -305,17 +305,66 @@ static int add_to_tar(struct dirtree *node)
return 0;
}
+ if (FLAG(sparse)) {
+ long long lo, ld = 0, len = 0;
+
+ // Enumerate the extents
+ while ((lo = lseek(fd, ld, SEEK_HOLE)) != -1) {
+ if (!(TT.sparselen&511))
+ TT.sparse = xrealloc(TT.sparse, (TT.sparselen+512)*sizeof(long long));
+ TT.sparse[TT.sparselen++] = ld;
+ len += TT.sparse[TT.sparselen++] = lo-ld;
+ if (lo == st->st_size) break;
+ if ((ld = lseek(fd, lo, SEEK_DATA)) < lo) ld = st->st_size;
+ }
+
+ // If there were extents, change type to S record
+ if (TT.sparselen>2) {
+ hdr.type = 'S';
+ lnk = (char *)&hdr;
+ for (i = 0; i<TT.sparselen && i<8; i++)
+ itoo(lnk+386+12*i, 12, TT.sparse[i]);
+
+ // Record if there's overflow records, change length to sparse length,
+ // record apparent length
+ if (TT.sparselen>8) lnk[482] = 1;
+ itoo(lnk+483, 12, st->st_size);
+ ITOO(hdr.size, len);
+ }
+ lseek(fd, 0, SEEK_SET);
+ }
}
itoo(hdr.chksum, sizeof(hdr.chksum)-1, cksum(&hdr));
hdr.chksum[7] = ' ';
- if (FLAG(v)) printf("%s\n", hname);
+ if (FLAG(v)) dprintf(TT.fd ? 2 : 1, "%s\n", hname);
// Write header and data to archive
xwrite(TT.fd, &hdr, 512);
- if (hdr.type == '0') {
- xsendfile_pad(fd, TT.fd, st->st_size);
+ if (TT.sparselen>8) {
+ char buf[512];
+
+ // write extent overflow blocks
+ for (i=8;;i++) {
+ int j = (i-8)%42;
+
+ if (!j || i==TT.sparselen) {
+ if (i!=8) xwrite(TT.fd, buf, 512);
+ if (i==TT.sparselen) break;
+ memset(buf, 0, sizeof(buf));
+ }
+ itoo(buf+12*j, 12, TT.sparse[i]);
+ }
+ }
+ TT.sparselen >>= 1;
+ if (hdr.type == '0' || hdr.type == 'S') {
+ if (hdr.type == '0') xsendfile_pad(fd, TT.fd, st->st_size);
+ else for (i = 0; i<TT.sparselen; i++) {
+ if (TT.sparse[i*2] != lseek(fd, TT.sparse[i*2], SEEK_SET))
+ perror_msg("%s: seek %lld", name, TT.sparse[i*2]);
+ xsendfile_pad(fd, TT.fd, TT.sparse[i*2+1]);
+ }
if (st->st_size%512) writeall(TT.fd, toybuf, (512-(st->st_size%512)));
close(fd);
}
@@ -567,7 +616,7 @@ static void unpack_tar(struct tar_hdr *first)
for (;;) {
if (!(TT.sparselen&511))
- TT.sparse = xrealloc(TT.sparse, (TT.sparselen+512)*sizeof(long));
+ TT.sparse = xrealloc(TT.sparse, (TT.sparselen+512)*sizeof(long long));
// If out of data in block check continue flag, stop or load next block
if (++i>max || !*s) {