Use POSIX file operations internally in tbdiff-create

This keeps the code consistent by using the same file functions
internally as are used when reading from or writing to the stream.

The code is also simplified somewhat since POSIX file operations
are cleaner and more consistent than stdio.

1 files changed, 35 insertions, 41 deletions

diff --git a/tbdiff/tbdiff-create.c b/tbdiff/tbdiff-create.c
index 1f0312a..0c5823d 100644
--- a/tbdiff/tbdiff-create.c
+++ b/tbdiff/tbdiff-create.c
@@ -16,13 +16,13 @@
  */
 
 #include <stdlib.h>
-#include <stdio.h>
 #include <string.h>
 #include <stdint.h>
 #include <stdbool.h>
 
 #include <sys/stat.h>
 #include <dirent.h>
+#include <fcntl.h>
 #include <unistd.h>
 
 #include "tbdiff-common.h"
@@ -236,20 +236,20 @@ tbd_create_cmd_file_create(int              stream,
 	if(!tbd_write_uint32(size, stream))
 		return TBD_ERROR(TBD_ERROR_UNABLE_TO_WRITE_STREAM);
 
-	FILE *fp = tbd_stat_fopen(f, "rb");
-	if(fp == NULL)
+	int fd = tbd_stat_open(f, O_RDONLY);
+	if(fd < 0)
 		return TBD_ERROR(TBD_ERROR_UNABLE_TO_OPEN_FILE_FOR_READING);
 
 	uint8_t buff[256];
 	uintptr_t b = 256;
 	for(b = 256; b == 256; ) {
-		b = fread(buff, 1, b, fp);
+		b = read(fd, buff, b);
 		if(write(stream, buff, b) != b) {
-			fclose(fp);
+			close(fd);
 			return TBD_ERROR(TBD_ERROR_UNABLE_TO_WRITE_STREAM);
 		}
 	}
-	fclose(fp);
+	close(fd);
 
 	return tbd_create_cmd_write_xattrs(stream, f);
 }
@@ -300,12 +300,12 @@ tbd_create_cmd_file_delta(int              stream,
                           struct tbd_stat *a,
                           struct tbd_stat *b)
 {
-	FILE *fpa = tbd_stat_fopen(a, "rb");
-	if(fpa == NULL)
+	int fda = tbd_stat_open(a, O_RDONLY);
+	if(fda < 0)
 		return TBD_ERROR(TBD_ERROR_UNABLE_TO_OPEN_FILE_FOR_READING);
-	FILE *fpb = tbd_stat_fopen(b, "rb");
-	if(fpb == NULL) {
-		fclose(fpa);
+	int fdb = tbd_stat_open(b, O_RDONLY);
+	if(fdb < 0) {
+		close(fda);
 		return TBD_ERROR(TBD_ERROR_UNABLE_TO_OPEN_FILE_FOR_READING);
 	}
 
@@ -315,8 +315,8 @@ tbd_create_cmd_file_delta(int              stream,
 
 	uintptr_t o;
 	for(o = 0; (blks[1] == blks[0]) && (blks[0] != 0); o += blks[1]) {
-		blks[0] = fread(buff[0], 1, blks[0], fpa);
-		blks[1] = fread(buff[1], 1, blks[0], fpb);
+		blks[0] = read(fda, buff[0], blks[0]);
+		blks[1] = read(fdb, buff[1], blks[0]);
 		if((blks[0] == 0) || (blks[1] == 0))
 			break;
 
@@ -332,20 +332,14 @@ tbd_create_cmd_file_delta(int              stream,
 	}
 	uint32_t start = o;
 
-	if((fseek(fpa, 0, SEEK_END) != 0) || (fseek(fpb, 0, SEEK_END) != 0)) {
-		fclose(fpa);
-		fclose(fpb);
-		return TBD_ERROR(TBD_ERROR_UNABLE_TO_SEEK_THROUGH_STREAM);
-	}
-
 	/* Find length. */
-	long flena = ftell(fpa);
-	long flenb = ftell(fpb);
+	off_t flena = lseek(fda, 0, SEEK_END);
+	off_t flenb = lseek(fdb, 0, SEEK_END);
 
 	if((flena < 0) || (flenb < 0)) {
-		fclose(fpa);
-		fclose(fpb);
-		return TBD_ERROR(TBD_ERROR_UNABLE_TO_DETECT_STREAM_POSITION);
+		close(fda);
+		close(fdb);
+		return TBD_ERROR(TBD_ERROR_UNABLE_TO_SEEK_THROUGH_STREAM);
 	}
 
 	/* Find end. */
@@ -357,17 +351,17 @@ tbd_create_cmd_file_delta(int              stream,
 		if((blks[0] == 0) || (blks[1] == 0))
 			break;
 
-		if((fseek(fpa, flena - (o + blks[0]), SEEK_SET) != 0)
-		    || (fseek(fpb, flenb - (o + blks[1]), SEEK_SET) != 0)) {
-			fclose(fpa);
-			fclose(fpb);
+		if((lseek(fda, flena - (o + blks[0]), SEEK_SET) < 0)
+		    || (lseek(fdb, flenb - (o + blks[1]), SEEK_SET) < 0)) {
+			close(fda);
+			close(fdb);
 			return TBD_ERROR(TBD_ERROR_UNABLE_TO_SEEK_THROUGH_STREAM);
 		}
 
-		if((fread(buff[0], 1, blks[0], fpa) != blks[0])
-		    || (fread(buff[1], 1, blks[1], fpb) != blks[1])) {
-			fclose(fpa);
-			fclose(fpb);
+		if((read(fda, buff[0], blks[0]) != blks[0])
+		    || (read(fdb, buff[1], blks[1]) != blks[1])) {
+			close(fda);
+			close(fdb);
 			return TBD_ERROR(TBD_ERROR_UNABLE_TO_READ_STREAM);
 		}
 
@@ -381,7 +375,7 @@ tbd_create_cmd_file_delta(int              stream,
 		if(i < blks[1])
 			break;
 	}
-	fclose(fpa);
+	close(fda);
 
 	/* Ensure that the start and end don't overlap for the new file. */
 	if((flenb - o) < start)
@@ -396,7 +390,7 @@ tbd_create_cmd_file_delta(int              stream,
 	/* Data is identical, only alter metadata */
 	if((end == start) && (size == 0)) {
 		tbd_create_cmd_file_metadata_update(stream, a, b);
-		fclose(fpb);
+		close(fdb);
 		return tbd_create_cmd_write_xattrs(stream, b);
 	}
 
@@ -411,7 +405,7 @@ tbd_create_cmd_file_delta(int              stream,
 	    ((err = tbd_create_write_uid   (stream, b->uid))            != 0) ||
 	    ((err = tbd_create_write_gid   (stream, b->gid))            != 0) ||
 	    ((err = tbd_create_write_mode  (stream, b->mode))           != 0)) {
-		fclose(fpb);
+		close(fdb);
 		return err;
 	}
 
@@ -421,24 +415,24 @@ tbd_create_cmd_file_delta(int              stream,
 		close(fdb);
 		return TBD_ERROR(TBD_ERROR_UNABLE_TO_WRITE_STREAM);
 	}
-	if(fseek(fpb, start, SEEK_SET) != 0) {
-		fclose(fpb);
+	if(lseek(fdb, start, SEEK_SET) < 0) {
+		close(fdb);
 		return TBD_ERROR(TBD_ERROR_UNABLE_TO_SEEK_THROUGH_STREAM);
 	}
 
 	for(o = 0; o < size; o += 256) {
 		uintptr_t csize = ((size - o) > 256 ? 256 : (size - o));
-		if(fread(buff[0], 1, csize, fpb) != csize) {
-			fclose(fpb);
+		if(read(fdb, buff[0], csize) != csize) {
+			close(fdb);
 			return TBD_ERROR(TBD_ERROR_UNABLE_TO_READ_STREAM);
 		}
 		if(write(stream, buff[0], csize) != csize) {
-			fclose(fpb);
+			close(fdb);
 			return TBD_ERROR(TBD_ERROR_UNABLE_TO_WRITE_STREAM);
 		}
 	}
 
-	fclose(fpb);
+	close(fdb);
 	return tbd_create_cmd_write_xattrs(stream, b);
 }