Updated files as per request.

Moved cookies etc from util.c to create.c, updated create* functions to use the cookies instead of hardcoded values.
Added docs/ folder with Microsoft VHD_CLEARBIT(x) specifications for completeness.
Fixed typos in Makefiles.

contrib/win32/Makefile.MinGW

@@ -8,7 +8,7 @@
 #
 #		Makefile for Windows systems using the MinGW32 environment.
 #
-# Version:	@(#)Makefile.MinGW	1.0.1	2021/03/16
+# Version:	@(#)Makefile.MinGW	1.0.2	2021/03/16
 #
 # Author:	Fred N. van Kempen, <waltje@varcem.com>
 #
@@ -55,7 +55,7 @@ ifndef X64
 endif
 
 
-PROGS		:= vhdcvt.exe
+PROGS		:= vhdcvt
 SYSOBJ		:=
 
 

src/create.c

@@ -3,9 +3,10 @@
  *
  *		This file is part of the MiniVHD Project.
  *
- * Version:	@(#)create.c	1.0.1	2021/03/16
+ * Version:	@(#)create.c	1.0.2	2021/03/16
  *
- * Author:	Sherman Perry, <shermperry@gmail.com>
+ * Authors:	Sherman Perry, <shermperry@gmail.com>
+ *		Fred N. van Kempen, <waltje@varcem.com>
  *
  *		Copyright 2019-2021 Sherman Perry.
  *
@@ -48,6 +49,12 @@
 #include "xml2_encoding.h"
 
 
+static const char MVHD_CONECTIX_COOKIE[] = "conectix";
+static const char MVHD_CREATOR[]	 = "mVHD";
+static const char MVHD_CREATOR_HOST_OS[] = "Wi2k";
+static const char MVHD_CXSPARSE_COOKIE[] = "cxsparse";
+
+
 /**
  * \brief Populate a VHD footer
  * 
@@ -60,20 +67,22 @@
 static void
 gen_footer(MVHDFooter* footer, uint64_t size_in_bytes, MVHDGeom* geom, MVHDType type, uint64_t sparse_header_off)
 {
-    memcpy(footer->cookie, "conectix", sizeof footer->cookie);
+    memcpy(footer->cookie, MVHD_CONECTIX_COOKIE, sizeof footer->cookie);
     footer->features = 0x00000002;
     footer->fi_fmt_vers = 0x00010000;
     footer->data_offset = (type == MVHD_TYPE_DIFF || type == MVHD_TYPE_DYNAMIC) ? sparse_header_off : 0xffffffffffffffff;
     footer->timestamp = vhd_calc_timestamp();
-    memcpy(footer->cr_app, "mvhd", sizeof footer->cr_app);
+    memcpy(footer->cr_app, MVHD_CREATOR, sizeof footer->cr_app);
     footer->cr_vers = 0x000e0000;
-    memcpy(footer->cr_host_os, "Wi2k", sizeof footer->cr_host_os);
+    memcpy(footer->cr_host_os, MVHD_CREATOR_HOST_OS, sizeof footer->cr_host_os);
     footer->orig_sz = footer->curr_sz = size_in_bytes;
     footer->geom.cyl = geom->cyl;
     footer->geom.heads = geom->heads;
     footer->geom.spt = geom->spt;
     footer->disk_type = type;
+
     mvhd_generate_uuid(footer->uuid);
+
     footer->checksum = mvhd_gen_footer_checksum(footer);
 }
 
@@ -89,7 +98,7 @@ gen_footer(MVHDFooter* footer, uint64_t size_in_bytes, MVHDGeom* geom, MVHDType
 static void
 gen_sparse_header(MVHDSparseHeader* header, uint32_t num_blks, uint64_t bat_offset, uint32_t block_size_in_sectors)
 {
-    memcpy(header->cookie, "cxsparse", sizeof header->cookie);
+    memcpy(header->cookie, MVHD_CXSPARSE_COOKIE, sizeof header->cookie);
     header->data_offset = 0xffffffffffffffff;
     header->bat_offset = bat_offset;
     header->head_vers = 0x00010000;
@@ -422,17 +431,21 @@ create_sparse_diff(const char* path, const char* par_path, uint64_t size_in_byte
      * */
     if (par_vhdm != NULL) {
         uint64_t curr_pos = (uint64_t)mvhd_ftello64(f);
+
         /* Double check my sums... */
         assert(curr_pos == par_loc_offset);
+
         /* Fill the space required for location data with zero */
         uint8_t empty_sect[MVHD_SECTOR_SIZE] = {0};
         int i;
         uint32_t j;
+
         for (i = 0; i < 2; i++) {
             for (j = 0; j < (vhdm->sparse.par_loc_entry[i].plat_data_space / MVHD_SECTOR_SIZE); j++) {
                 fwrite(empty_sect, sizeof empty_sect, 1, f);
             }
         }
+
         /* Now write the location entries */
         mvhd_fseeko64(f, vhdm->sparse.par_loc_entry[0].plat_data_offset, SEEK_SET);
         fwrite(w2ku_path_buff, vhdm->sparse.par_loc_entry[0].plat_data_len, 1, f);
@@ -457,8 +470,9 @@ cleanup_vhdm:
     vhdm = NULL;
 
 cleanup_par_vhdm:
-    if (par_vhdm != NULL)
+    if (par_vhdm != NULL) {
         mvhd_close(par_vhdm);
+    }
 
 end:    
     free(w2ku_path_buff);    
@@ -552,3 +566,14 @@ mvhd_create_ex(MVHDCreationOptions options, int* err)
 
     return NULL; /* Make the compiler happy */
 }
+
+
+bool
+mvhd_is_conectix_str(const void* buffer)
+{
+    if (strncmp(buffer, MVHD_CONECTIX_COOKIE, strlen(MVHD_CONECTIX_COOKIE)) == 0) {
+        return true;
+    }
+
+    return false;
+}

src/cwalk.c

@@ -1,13 +1,13 @@
 /*
- * MiniVHD	Minimalist VHD implementation in C.
+ * libCWALK	Path library for C/C++
  *
- *		This file is part of the MiniVHD Project.
+ * Version:	@(#)cwalk.c	1.0.2	2021/03/16
  *
- * Version:	@(#)cwalk.c	1.0.1	2021/03/15
- *
- * Author:	Sherman Perry, <shermperry@gmail.com>
+ * Authors:	Sherman Perry, <shermperry@gmail.com>
+ *		Leonard Iklé, <https://github.com/likle>
  *
  *		Copyright 2019-2021 Sherman Perry.
+ *		Copyright 2020 Leonard Iklé.
  *
  *		MIT License
  *

src/cwalk.h

@@ -1,13 +1,13 @@
 /*
- * MiniVHD	Minimalist VHD implementation in C.
+ * libCWALK	path library for C/C++
  *
- *		This file is part of the MiniVHD Project.
+ * Version:	@(#)cwalk.c	1.0.2	2021/03/16
  *
- * Version:	@(#)cwalk.c	1.0.1	2021/03/15
- *
- * Author:	Sherman Perry, <shermperry@gmail.com>
+ * Authors:	Sherman Perry, <shermperry@gmail.com>
+ *		Leonard Iklé, <https://github.com/likle>
  *
  *		Copyright 2019-2021 Sherman Perry.
+ *		Copyright 2020 Leonard Iklé.
  *
  *		MIT License
  *

src/io.c

@@ -5,7 +5,7 @@
  *
  *		Sector reading and writing implementations.
  *
- * Version:	@(#)io.c	1.0.1	2021/03/16
+ * Version:	@(#)io.c	1.0.2	2021/03/16
  *
  * Author:	Sherman Perry, <shermperry@gmail.com>
  *
@@ -83,6 +83,7 @@ mvhd_write_empty_sectors(FILE* f, int sector_count)
 {
     uint8_t zero_bytes[MVHD_SECTOR_SIZE] = {0};
     int i;
+
     for (i = 0; i < sector_count; i++) {
         fwrite(zero_bytes, sizeof zero_bytes, 1, f);
     }
@@ -104,8 +105,9 @@ read_sect_bitmap(MVHDMeta* vhdm, int blk)
     if (vhdm->block_offset[blk] != MVHD_SPARSE_BLK) {
         mvhd_fseeko64(vhdm->f, (uint64_t)vhdm->block_offset[blk] * MVHD_SECTOR_SIZE, SEEK_SET);
         fread(vhdm->bitmap.curr_bitmap, vhdm->bitmap.sector_count * MVHD_SECTOR_SIZE, 1, vhdm->f);
-    } else
+    } else {
         memset(vhdm->bitmap.curr_bitmap, 0, vhdm->bitmap.sector_count * MVHD_SECTOR_SIZE);
+    }
 
     vhdm->bitmap.curr_block = blk;
 }
@@ -167,6 +169,7 @@ create_block(MVHDMeta* vhdm, int blk)
     mvhd_fseeko64(vhdm->f, -MVHD_FOOTER_SIZE, SEEK_END);
     fread(footer, sizeof footer, 1, vhdm->f);
     mvhd_fseeko64(vhdm->f, -MVHD_FOOTER_SIZE, SEEK_END);
+
     if (!mvhd_is_conectix_str(footer)) {
         /* Oh dear. We use the header instead, since something has gone wrong at the footer */
         mvhd_fseeko64(vhdm->f, 0, SEEK_SET);

src/manage.c

@@ -5,7 +5,7 @@
  *
  *		VHD management functions (open, close, read write etc)
  *
- * Version:	@(#)manage.c	1.0.1	2021/03/16
+ * Version:	@(#)manage.c	1.0.2	2021/03/16
  *
  * Author:	Sherman Perry, <shermperry@gmail.com>
  *
@@ -172,8 +172,9 @@ calc_sparse_values(MVHDMeta* vhdm)
     int bm_bytes = vhdm->sect_per_block / 8;
     vhdm->bitmap.sector_count = bm_bytes / MVHD_SECTOR_SIZE;
 
-    if (bm_bytes % MVHD_SECTOR_SIZE > 0)
+    if (bm_bytes % MVHD_SECTOR_SIZE > 0) {
         vhdm->bitmap.sector_count++;
+    }
 }
 
 
@@ -225,7 +226,8 @@ static bool
 mvhd_parent_path_exists(struct MVHDPaths* paths, uint32_t plat_code)
 {
     FILE* f;
-    int cwk_ret, ferr;
+    int ferr;
+    size_t cwk_ret;
     enum cwk_path_style style;
 
     memset(paths->joined_path, 0, sizeof paths->joined_path);
@@ -234,15 +236,16 @@ mvhd_parent_path_exists(struct MVHDPaths* paths, uint32_t plat_code)
     cwk_ret = 1;
 
     if (plat_code == MVHD_DIF_LOC_W2RU && *paths->w2ru_path) {
-        cwk_ret = (int)cwk_path_join((const char*)paths->dir_path, (const char*)paths->w2ru_path, paths->joined_path, sizeof paths->joined_path);
+        cwk_ret = cwk_path_join((const char*)paths->dir_path, (const char*)paths->w2ru_path, paths->joined_path, sizeof paths->joined_path);
     } else if (plat_code == MVHD_DIF_LOC_W2KU && *paths->w2ku_path) {
         memcpy(paths->joined_path, paths->w2ku_path, (sizeof paths->joined_path) - 1);
         cwk_ret = 0;
     } else if (plat_code == 0) {
-        cwk_ret = (int)cwk_path_join((const char*)paths->dir_path, (const char*)paths->file_name, paths->joined_path, sizeof paths->joined_path);
+        cwk_ret = cwk_path_join((const char*)paths->dir_path, (const char*)paths->file_name, paths->joined_path, sizeof paths->joined_path);
     }
-    if (cwk_ret > MVHD_MAX_PATH_BYTES)
+    if (cwk_ret > MVHD_MAX_PATH_BYTES) {
         return false;
+    }
 
     f = mvhd_fopen((const char*)paths->joined_path, "rb", &ferr);
     if (f != NULL) {
@@ -318,8 +321,9 @@ get_diff_parent_path(MVHDMeta* vhdm, int* err)
             loc_path = (unsigned char*)paths->w2ru_path;
         } else if (vhdm->sparse.par_loc_entry[i].plat_code == MVHD_DIF_LOC_W2KU) {
             loc_path = (unsigned char*)paths->w2ku_path;
-        } else
+        } else {
             continue;
+	}
 
         utf_inlen = vhdm->sparse.par_loc_entry[i].plat_data_len;
         if (utf_inlen > MVHD_MAX_PATH_BYTES) {
@@ -437,13 +441,15 @@ mvhd_file_is_vhd(FILE* f)
 {
     uint8_t con_str[8];
 
-    if (f == NULL)
+    if (f == NULL) {
 	return 0;
+    }
 
     mvhd_fseeko64(f, -MVHD_FOOTER_SIZE, SEEK_END);
     fread(con_str, sizeof con_str, 1, f);
-    if (mvhd_is_conectix_str(con_str))
+    if (mvhd_is_conectix_str(con_str)) {
 	return 1;
+    }
 
     return 0;
 }
@@ -511,10 +517,11 @@ mvhd_open(const char* path, int readonly, int* err)
     //This is safe, as we've just checked for potential overflow above
     strcpy(vhdm->filename, path);
 
-    if (readonly)
+    if (readonly) {
 	vhdm->f = mvhd_fopen((const char*)vhdm->filename, "rb", err);
-    else
+    } else {
 	vhdm->f = mvhd_fopen((const char*)vhdm->filename, "rb+", err);
+    }
     if (vhdm->f == NULL) {
         /* note, mvhd_fopen sets err for us */
         goto cleanup_vhdm;

src/util.c

@@ -5,7 +5,7 @@
  *
  *		Utility functions.
  *
- * Version:	@(#)util.c	1.0.1	2021/03/16
+ * Version:	@(#)util.c	1.0.2	2021/03/16
  *
  * Author:	Sherman Perry, <shermperry@gmail.com>
  *
@@ -52,14 +52,6 @@
 #include "xml2_encoding.h"
 
 
-static const char MVHD_CONECTIX_COOKIE[] = "conectix";
-#if 0	//NOT_USED
-static const char MVHD_CREATOR[] = "MiniVHD";
-static const char MVHD_CREATOR_HOST_OS[] = "Wi2k";
-static const char MVHD_CXSPARSE_COOKIE[] = "cxsparse";
-#endif
-
-
 uint16_t
 mvhd_from_be16(uint16_t val)
 {
@@ -154,17 +146,6 @@ mvhd_to_be64(uint64_t val)
 }
 
 
-bool
-mvhd_is_conectix_str(const void* buffer)
-{
-    if (strncmp(buffer, MVHD_CONECTIX_COOKIE, strlen(MVHD_CONECTIX_COOKIE)) == 0) {
-        return true;
-    }
-
-    return false;
-}
-
-
 void
 mvhd_generate_uuid(uint8_t* uuid)
 {

src/win32/Makefile.MinGW

@@ -10,7 +10,7 @@
 #
 #		Makefile for Windows systems using the MinGW32 environment.
 #
-# Version:	@(#)Makefile.MinGW	1.0.1	2021/03/16
+# Version:	@(#)Makefile.MinGW	1.0.2	2021/03/16
 #
 # Author:	Fred N. van Kempen, <waltje@varcem.com>
 #
@@ -170,7 +170,7 @@ SYSLIBS		+= -static -lgcc
 
 # Final versions of the toolchain flags.
 CFLAGS		:= $(OPTS) $(DFLAGS) $(COPTIM) $(AOPTIM) -I. \
-		   $(AFLAGS) -fomit-frame-pointer -mstackrealign
+		   $(AFLAGS) -fomit-frame-pointer -mstackrealign \
 		   -Wall -Wundef -Wshadow -Wunused-parameter \
 		   -Wmissing-declarations
 LFLAGS		:= -L.