abuild-gzsplit: new tool to split .apk to it's base components

required tool for re-signing packages

2 files changed, 83 insertions, 2 deletions

diff --git a/Makefile b/Makefile
index 0006b0f..279f458 100644
--- a/Makefile
+++ b/Makefile
@@ -10,7 +10,7 @@ datadir		?= $(prefix)/share/$(PACKAGE)
 SCRIPTS		:= abuild abuild-keygen abuild-sign newapkbuild \
 		   abump apkgrel buildlab apkbuild-cpan checkapk \
 		   apkbuild-gem-resolver
-USR_BIN_FILES	:= $(SCRIPTS) abuild-tar abuild-sudo abuild-fetch
+USR_BIN_FILES	:= $(SCRIPTS) abuild-tar abuild-gzsplit abuild-sudo abuild-fetch
 SAMPLES		:= sample.APKBUILD sample.initd sample.confd \
 		sample.pre-install sample.post-install
 AUTOTOOLS_TOOLCHAIN_FILES := config.sub config.guess
@@ -38,13 +38,16 @@ SED_REPLACE	:= -e 's:@VERSION@:$(FULL_VERSION):g' \
 SSL_CFLAGS	?= $(shell pkg-config --cflags openssl)
 SSL_LDFLAGS	?= $(shell pkg-config --cflags openssl)
 SSL_LIBS	?= $(shell pkg-config --libs openssl)
-
+ZLIB_LIBS	?= $(shell pkg-config --libs zlib)
 
 OBJS-abuild-tar  = abuild-tar.o
 CFLAGS-abuild-tar.o = $(SSL_CFLAGS)
 LDFLAGS-abuild-tar = $(SSL_LDFLAGS)
 LIBS-abuild-tar = $(SSL_LIBS)
 
+OBJS-abuild-gzsplit = abuild-gzsplit.o
+LDFLAGS-abuild-gzsplit = $(ZLIB_LIBS)
+
 OBJS-abuild-sudo = abuild-sudo.o
 OBJS-abuild-fetch = abuild-fetch.o
 
@@ -76,6 +79,9 @@ abuild-tar: abuild-tar.o
 abuild-fetch: abuild-fetch.o
 	$(LINK)
 
+abuild-gzsplit: abuild-gzsplit.o
+	$(LINK)
+
 abuild-tar.static: abuild-tar.o
 	$(CC) $(CPPFLAGS) $(CFLAGS) $(CFLAGS-$@) -o $@ -static $(LIBS-$@) $^
 
diff --git a/abuild-gzsplit.c b/abuild-gzsplit.c
new file mode 100644
index 0000000..5e7a698
--- /dev/null
+++ b/abuild-gzsplit.c
@@ -0,0 +1,75 @@
+#include <stdio.h>
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <zlib.h>
+
+int main(void)
+{
+	char obuf[8*1024], ibuf[8*1024];
+	z_stream zs;
+	int r = Z_OK, rc = 1, fd = -1;
+	size_t len;
+
+	if (inflateInit2(&zs, 15+32) != Z_OK)
+		goto err;
+
+	zs.avail_out = sizeof obuf;
+	zs.next_out  = obuf;
+
+	while (1) {
+		if (zs.avail_in == 0) {
+			zs.avail_in = read(STDIN_FILENO, ibuf, sizeof ibuf);
+			zs.next_in = ibuf;
+			if (zs.avail_in < 0) goto err;
+			if (zs.avail_in == 0 && r == Z_STREAM_END) goto ok;
+		}
+
+		r = inflate(&zs, Z_NO_FLUSH);
+		if (r != Z_OK && r != Z_STREAM_END) goto err;
+
+		len = sizeof obuf - zs.avail_out;
+		if (len) {
+			if (fd < 0) {
+				const char *fn;
+				if (strncmp(obuf, ".SIGN.", 6) == 0)
+					fn = "signatures.tar.gz";
+				else if (strncmp(obuf, ".PKGINFO", 8) == 0)
+					fn = "control.tar.gz";
+				else if (rc == 1)
+					fn = "data.tar.gz", rc = 2;
+				else
+					goto err;
+				fd = open(fn, O_CREAT|O_TRUNC|O_WRONLY, 0777);
+				if (fd < 0) goto err;
+			}
+			zs.next_out = obuf;
+			zs.avail_out = sizeof obuf;
+		}
+
+		if (zs.avail_in == 0 || r == Z_STREAM_END) {
+			len = (void *)zs.next_in - (void *)ibuf;
+			if (write(fd, ibuf, len) != len) goto err;
+			memmove(ibuf, zs.next_in, zs.avail_in);
+			zs.next_in = ibuf;
+		}
+
+		if (r == Z_STREAM_END) {
+			if (fd >= 0) {
+				close(fd);
+				fd = -1;
+			}
+			inflateEnd(&zs);
+			if (inflateInit2(&zs, 15+32) != Z_OK) goto err;
+		}
+	}
+ok:
+	rc = 0;
+err:
+	if (fd >= 0) close(fd);
+	inflateEnd(&zs);
+	if (rc) fprintf(stderr, "failed\n");
+	return rc;
+}
+