libdpkg: Add new dpkg ar support functions

lib/dpkg/ar.c

@@ -21,6 +21,15 @@
 #include <config.h>
 #include <compat.h>
 
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <time.h>
+#include <unistd.h>
+
+#include <dpkg/i18n.h>
+#include <dpkg/dpkg.h>
+#include <dpkg/buffer.h>
 #include <dpkg/ar.h>
 
 void
@@ -37,3 +46,57 @@ dpkg_ar_normalize_name(struct ar_hdr *arh)
 	if (name[i] == '/')
 		name[i] = '\0';
 }
+
+void
+dpkg_ar_put_magic(const char *ar_name, int ar_fd)
+{
+	if (write(ar_fd, DPKG_AR_MAGIC, strlen(DPKG_AR_MAGIC)) < 0)
+		ohshite(_("unable to write file '%s'"), ar_name);
+}
+
+void
+dpkg_ar_member_put_header(const char *ar_name, int ar_fd,
+                          const char *name, size_t size)
+{
+	char header[sizeof(struct ar_hdr)];
+
+	sprintf(header, "%-16s%-12lu0     0     100644  %-10lu`\n",
+	        name, time(NULL), (unsigned long)size);
+
+	if (write(ar_fd, header, sizeof(header)) < 0)
+		ohshite(_("unable to write file '%s'"), ar_name);
+}
+
+void
+dpkg_ar_member_put_mem(const char *ar_name, int ar_fd,
+                       const char *name, const void *data, size_t size)
+{
+	dpkg_ar_member_put_header(ar_name, ar_fd, name, size);
+
+	/* Copy data contents. */
+	if (write(ar_fd, data, size) < 0)
+		ohshite(_("unable to write file '%s'"), ar_name);
+
+	if (size & 1)
+		if (write(ar_fd, "\n", 1) < 0)
+			ohshite(_("unable to write file '%s'"), ar_name);
+}
+
+void
+dpkg_ar_member_put_file(const char *ar_name, int ar_fd,
+                        const char *name, int fd)
+{
+	struct stat st;
+
+	if (fstat(fd, &st))
+		ohshite(_("failed to fstat ar member file (%s)"), name);
+
+	dpkg_ar_member_put_header(ar_name, ar_fd, name, st.st_size);
+
+	/* Copy data contents. */
+	fd_fd_copy(fd, ar_fd, -1, name);
+
+	if (st.st_size & 1)
+		if (write(ar_fd, "\n", 1) < 0)
+			ohshite(_("unable to write file '%s'"), ar_name);
+}

lib/dpkg/ar.h

@@ -31,6 +31,14 @@ DPKG_BEGIN_DECLS
 
 void dpkg_ar_normalize_name(struct ar_hdr *arh);
 
+void dpkg_ar_put_magic(const char *ar_name, int ar_fd);
+void dpkg_ar_member_put_header(const char *ar_name, int ar_fd,
+                               const char *name, size_t size);
+void dpkg_ar_member_put_file(const char *ar_name, int ar_fd, const char *name,
+                             int fd);
+void dpkg_ar_member_put_mem(const char *ar_name, int ar_fd, const char *name,
+                            const void *data, size_t size);
+
 DPKG_END_DECLS
 
 #endif /* LIBDPKG_AR_H */

lib/dpkg/libdpkg.Versions

@@ -108,6 +108,12 @@ LIBDPKG_PRIVATE {
 	compress_filter;
 	decompress_filter;
 
+	# Ar support
+	dpkg_ar_put_magic;
+	dpkg_ar_member_put_header;
+	dpkg_ar_member_put_file;
+	dpkg_ar_member_put_mem;
+
 	# Configuration and command line handling
 	loadcfgfile;
 	myopt;