library api: tpax_archive_seal(): initial implementation and integration.

1 files changed, 64 insertions, 5 deletions

diff --git a/src/logic/tpax_archive_append.c b/src/logic/tpax_archive_append.c
index ce357b5..dfdd92c 100644
--- a/src/logic/tpax_archive_append.c
+++ b/src/logic/tpax_archive_append.c
@@ -1,3 +1,4 @@
+
 /******************************************************/
 /*  tpax: a topological pax implementation            */
 /*  Copyright (C) 2020  Z. Gilboa                     */
@@ -48,9 +49,12 @@ static int tpax_archive_append_memory_data(
 }
 
 static int tpax_archive_append_pad(
-	int                     fdout,
-	const struct stat *     st)
+	const struct tpax_driver_ctx *  dctx,
+	int                             fdout,
+	const struct stat *             st)
 {
+	int     ret;
+	off_t   cpos;
 	ssize_t nbytes;
 	char    buf[512];
 
@@ -62,8 +66,13 @@ static int tpax_archive_append_pad(
 
 	memset(buf,0,nbytes);
 
-	return tpax_archive_append_memory_data(
-		fdout,buf,nbytes);
+	cpos  = tpax_get_driver_cpos(dctx);
+	cpos += st->st_size + nbytes;
+
+	if (!(ret = tpax_archive_append_memory_data(fdout,buf,nbytes)))
+		tpax_set_driver_cpos(dctx,cpos);
+
+	return ret;
 }
 
 int tpax_archive_append(
@@ -71,6 +80,8 @@ int tpax_archive_append(
 	const struct tpax_unit_ctx *    uctx)
 {
 	struct tpax_ustar_header        uhdr;
+	off_t                           hpos;
+	off_t                           dpos;
 	int                             fdout;
 	int                             fdtmp;
 	ssize_t                         nread;
@@ -89,6 +100,10 @@ int tpax_archive_append(
 	/* driver */
 	fdout = tpax_driver_fdout(dctx);
 
+	/* header and data offsets: todo pax and cpio */
+	hpos = tpax_get_driver_cpos(dctx);
+	dpos = hpos + sizeof(uhdr);
+
 	/* header */
 	if (tpax_init_ustar_header(
 			dctx,*uctx->path,uctx->st,
@@ -130,6 +145,8 @@ int tpax_archive_append(
 		return TPAX_SYSTEM_ERROR(dctx);
 	}
 
+	tpax_set_driver_cpos(dctx,dpos);
+
 	/* append data from snapshot */
 	if (fdtmp >= 0) {
 		if (!buf) {
@@ -170,5 +187,47 @@ int tpax_archive_append(
 	}
 
 	return tpax_archive_append_pad(
-		fdout,uctx->st);
+		dctx,fdout,uctx->st);
+}
+
+int tpax_archive_seal(const struct tpax_driver_ctx * dctx)
+{
+	int     fdout;
+	off_t   cpos;
+	ssize_t nbytes;
+	ssize_t nwritten;
+	ssize_t blksize;
+	char    buf[512];
+
+	blksize = tpax_get_archive_block_size(dctx);
+	cpos    = tpax_get_driver_cpos(dctx);
+
+	if (cpos % 512)
+		return TPAX_CUSTOM_ERROR(dctx,TPAX_ERR_FLOW_ERROR);
+
+	fdout = tpax_driver_fdout(dctx);
+	memset(buf,0,sizeof(buf));
+
+	switch (cpos % blksize) {
+		case 0:
+			nbytes = cpos + blksize;
+			break;
+
+		default:
+			nbytes  = cpos / blksize;
+			nbytes *= blksize;
+			nbytes += blksize;
+
+			if (nbytes-cpos == 512)
+				nbytes += blksize;
+	}
+
+	for (nwritten=cpos; nwritten<nbytes; nwritten+=512) {
+		if (tpax_archive_append_memory_data(fdout,buf,512) < 0)
+			return TPAX_SYSTEM_ERROR(dctx);
+
+		tpax_set_driver_cpos(dctx,nwritten);
+	}
+
+	return 0;
 }