Initial sketch of file access wrappers.

It compiles but does nothing useful yet. The "//" comments are notes to 
remember what to do in each block.

2 files changed, 369 insertions, 0 deletions

diff --git a/source/blender/blenlib/BLI_bfile.h b/source/blender/blenlib/BLI_bfile.h
new file mode 100644
index 00000000000..92543558a19
--- /dev/null
+++ b/source/blender/blenlib/BLI_bfile.h
@@ -0,0 +1,138 @@
+/*
+ * $Id$
+ *
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * The Original Code is Copyright (C) 2009 by Stichting Blender Foundation.
+ * All rights reserved.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ * BFILE* based abstraction of file access.
+ */
+
+#ifndef BLI_BFILE_H
+#define BLI_BFILE_H
+
+/* For fopen's FILE */
+#include <stdio.h>
+
+/**
+ Defines for the bflags param.
+ */
+/* Special handling: */
+/* For "symmetry" of flags */
+#define BFILE_NORMAL (0)
+/* No supervision, just translate // if needed, RISKY */
+#define BFILE_RAW    (1<<0)
+/* Path is relative to config dirs */
+#define BFILE_CONFIG (1<<1)
+/* Path is for current session temp file */
+#define BFILE_TEMP   (1<<2)
+
+/* Config handling, special cases: */
+#define BFILE_USERONLY (1<<3)
+#define BFILE_SYSONLY  (1<<4)
+
+/* Compression to apply on close: */
+#define BFILE_GZIP (1<<5)
+
+/**
+ File descriptor for Blender abstracted file access.
+ */
+typedef struct {
+	FILE *stream;
+	int fd;
+
+	/* Anything below should not be touched directly */
+	int uflags;  /* Special options requested by upper level, copy of bflags */
+	char *fpath; /* Final/requested path name */
+	char *tpath; /* Temp path name if applicable */
+	int type;    /* Own flags, common classification of open and fopen */
+	int error;   /* An op caused an error, unsafe to replace older files */
+} BFILE;
+
+/**
+ Open a BFILE* with fopen()-like syntax.
+ */
+BFILE *BLI_bfile_fopen(const char *path, const char *mode, int bflags);
+
+/**
+ Open a BFILE* with open()-like syntax.
+ */
+BFILE *BLI_bfile_open(const char *pathname, int flags, int bflags);
+
+/**
+ Get the FILE* associated with the BFILE*.
+ */
+FILE *BLI_bfile_file_from_bfile(BFILE *bfile);
+
+/**
+ Get the fd associated with the BFILE*.
+ */
+int BLI_bfile_fd_from_bfile(BFILE *bfile);
+
+/**
+ write()-like using BFILE*.
+ */
+ssize_t BLI_bfile_write(BFILE *f, const void *buf, size_t count);
+
+/**
+ read()-like using BFILE*.
+ */
+ssize_t BLI_bfile_read(BFILE *f, void *buf, size_t count);
+
+/**
+ fwrite()-like using BFILE*.
+ */
+size_t BLI_bfile_fwrite(const void *ptr, size_t size, size_t nmemb, BFILE *f);
+
+/**
+ fread()-like using BFILE*.
+ */
+size_t BLI_bfile_fread(void *ptr, size_t size, size_t nmemb, BFILE *f);
+
+/**
+ Close a BFILE, to match close() and fclose().
+ */
+void BLI_bfile_close(BFILE *bfile);
+
+/**
+ Clear error status.
+ Call it only if the error has been really handled.
+ */
+void BLI_bfile_clear_error(BFILE *bfile);
+
+/**
+ Set the error status.
+ Call it to mark writing by a 3rd party failed (libjpeg reported error, ie).
+ */
+void BLI_bfile_set_error(BFILE *bfile, int error);
+
+/*
+TODO
+Maybe also provide more OS/libc things like:
+fflush
+fprintf and related
+fscanf
+fgetc/fputc and related
+fseek and related
+
+Probably good to do:
+readdir (compacted list showing all files for a "directory" (user versions on top of system's))
+*/
+
+#endif /* ifndef BLI_BFILE_H */
diff --git a/source/blender/blenlib/intern/BLI_bfile.c b/source/blender/blenlib/intern/BLI_bfile.c
new file mode 100644
index 00000000000..06e75a9a3ca
--- /dev/null
+++ b/source/blender/blenlib/intern/BLI_bfile.c
@@ -0,0 +1,231 @@
+/*
+ * $Id$
+ *
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * The Original Code is Copyright (C) 2009 by Stichting Blender Foundation.
+ * All rights reserved.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ * BFILE* based abstraction for file access.
+ */
+
+#include <string.h>
+
+#include <unistd.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include "MEM_guardedalloc.h"
+
+#include "BLI_bfile.h"
+
+// This would provide config paths and their oldest viable version
+// so if there is an uncompatible change, user's old versions are not loaded
+//#include "bfile_tables.h"
+
+/* Internal bfile type flags */
+#define BTF_OPEN     (0)
+#define BTF_FOPEN    (1<<0)
+#define BTF_READ     (1<<1)
+#define BTF_WRITE    (1<<2)
+#define BTF_AT_END   (1<<3)
+#define BTF_DISCARD  (1<<4)
+
+
+void fill_paths(BFILE *bfile, const char *path) {
+	char* source_path = NULL;
+	int bflags = bfile->uflags;
+
+	if(bflags & BFILE_NORMAL || bflags & BFILE_RAW) {
+//		bfile->fpath is path with // replaced
+	}
+	if(bflags & BFILE_TEMP) {
+//		bfile->fpath is tempdir+path
+	}
+	if(bflags & BFILE_CONFIG) {
+//		bfile->fpath is userdir+version+path
+//		source_path is first hit in (if using fallback to older versions)
+//		    userdir+curversion+path (... userdir+limitversion+path) sysdir+path
+//		(limitversion is based in path, using some kind of regex or "tables")
+	}
+
+	if(bfile->type & BTF_WRITE && !(bflags & BFILE_RAW)) {
+		/* Generate temp path */
+		// bfile->tpath is fpath+randstring
+		if(!(bfile->type & BTF_DISCARD)) {
+			/* Copy data to tpath */
+			if(source_path) {
+				// copy it from older version or sys version
+			}
+		}
+	} else {
+		bfile->tpath = bfile->fpath;
+	}
+}
+
+BFILE *BLI_bfile_fopen(const char *path, const char *mode, int bflags) {
+	BFILE *bfile;
+
+	bfile = MEM_mallocN(sizeof(BFILE), "bfile-fopen");
+	bfile->type = BTF_FOPEN;
+	bfile->uflags = bflags;
+
+	/* From fopen() doc, we can guess some logic:
+	r  BTF_READ
+	r+ BTF_READ | BTF_WRITE
+	w  BTF_DISCARD | BTF_WRITE
+	w+ BTF_DISCARD | BTF_WRITE | BTF_READ
+	a  BTF_AT_END | BTF_WRITE
+	a+ BTF_AT_END | BTF_WRITE | BTF_READ
+	*/
+	if(strchr(mode, 'r'))
+		bfile->type |= BTF_READ;
+	if(strchr(mode, 'w'))
+		bfile->type |= (BTF_DISCARD | BTF_WRITE);
+	if(strchr(mode, 'a'))
+		bfile->type |= (BTF_AT_END | BTF_WRITE);
+	if(strchr(mode, '+'))
+		bfile->type |= (BTF_READ | BTF_WRITE);
+
+	fill_paths(bfile, path);
+
+	bfile->stream = fopen(bfile->tpath, mode);
+	// detect failed fopen
+	bfile->fd = fileno(bfile->stream);
+	return bfile;
+}
+
+
+BFILE *BLI_bfile_open(const char *pathname, int flags, int bflags) {
+	BFILE *bfile;
+
+	bfile = MEM_mallocN(sizeof(BFILE), "bfile-open");
+	bfile->type = BTF_OPEN;
+	bfile->uflags = bflags;
+
+	/* Easy mapping for open() */
+	if(flags & O_RDONLY)
+		bfile->type |= BTF_READ;
+	if(flags & O_WRONLY)
+		bfile->type |= BTF_WRITE;
+	if(flags & O_RDWR)
+		bfile->type |= (BTF_READ | BTF_WRITE);
+	if(flags & O_APPEND)
+		bfile->type |= BTF_AT_END;
+	if(flags & O_TRUNC)
+		bfile->type |= BTF_DISCARD;
+
+	fill_paths(bfile, pathname);
+
+	bfile->fd = open(bfile->tpath, flags);
+	// detect failed open
+//	bfile->stream = fdopen(bfile->fd, XXX); /* MSWindows _fdopen? */
+	return bfile;
+}
+
+
+FILE *BLI_bfile_file_from_bfile(BFILE *bfile) {
+	return bfile->stream;
+}
+
+
+int BLI_bfile_fd_from_bfile(BFILE *bfile) {
+	return bfile->fd;
+}
+
+
+ssize_t BLI_bfile_write(BFILE *f, const void *buf, size_t count) {
+	ssize_t ret;
+
+	ret = write((f->fd), buf, count);
+	if (ret == -1) {
+		f->error = 1;
+	}
+
+	return ret;
+}
+
+
+ssize_t BLI_bfile_read(BFILE *f, void *buf, size_t count) {
+	ssize_t ret;
+
+	ret = read((f->fd), buf, count);
+	if (ret == -1) {
+		f->error = 1;
+	}
+
+	return ret;
+}
+
+
+size_t BLI_bfile_fwrite(const void *ptr, size_t size, size_t nmemb, BFILE *f) {
+	size_t ret;
+
+	ret = fwrite(ptr, size, nmemb, f->stream);
+	if (ret < 0) {
+		f->error = 1;
+	}
+
+	return ret;
+}
+
+
+size_t BLI_bfile_fread(void *ptr, size_t size, size_t nmemb, BFILE *f) {
+	size_t ret;
+
+	ret = fread(ptr, size, nmemb, f->stream);
+	if ((ret < 0) && ferror(f->stream)) {
+		f->error = 1;
+	}
+
+	return ret;
+}
+
+
+void BLI_bfile_close(BFILE *bfile) {
+	if((bfile->type | BTF_WRITE) &&
+	   !(bfile->uflags | BFILE_RAW)) {
+		/* Make sure data is on disk */
+		/* Move to final name if no errors */
+	}
+
+	/* Normal close */
+
+	/* Cleanup */
+	if(bfile->fpath) {
+		MEM_freeN(bfile->fpath);
+	}
+	if(bfile->tpath) {
+		MEM_freeN(bfile->tpath);
+	}
+}
+
+
+void BLI_bfile_clear_error(BFILE *bfile) {
+	bfile->error = 0;
+}
+
+
+void BLI_bfile_set_error(BFILE *bfile, int error) {
+	/* No cheating, use clear_error() for 0 */
+	if (error) {
+		bfile->error = error;
+	}
+}