X-Git-Url: https://git.draconx.ca/gitweb/upkg.git/blobdiff_plain/79dd803a930da414ec5af1bf41e36317e601fac7..90b53df329f9a114770dccab6b7e41f9094dfac9:/src/libupkg.c

diff --git a/src/libupkg.c b/src/libupkg.c
index 66546fd..f2addc9 100644
--- a/src/libupkg.c
+++ b/src/libupkg.c
@@ -47,6 +47,8 @@ struct upkg_import {
 struct upkg_private {
 	FILE *f;
 
+	struct upkg_file *last_file;
+
 	struct upkg_name   *names;
 	struct upkg_export *exports;
 	struct upkg_import *imports;
@@ -60,7 +62,7 @@ struct upkg_private {
  * Stores the result in *val and returns the number of input bytes read (or 0
  * if the input is invalid, in which case *val is undefined).
  */
-static size_t decode_index(long *val, unsigned char *bytes, size_t n)
+size_t upkg_decode_index(long *val, unsigned char *bytes, size_t n)
 {
 	size_t i = 0;
 
@@ -122,6 +124,34 @@ static struct upkg *init_upkg(unsigned char hdr[static UPKG_HDR_SIZE])
 	return &alloc->pkg;
 }
 
+static int pkg_init_guid(struct upkg *pkg)
+{
+	size_t rc;
+
+	if (pkg->version < 68) {
+		unsigned long heritage_count, heritage_offset;
+		unsigned char buf[8];
+
+		rc = fread(buf, 1, sizeof buf, pkg->priv->f);
+		if (rc < 8)
+			return -1;
+
+		heritage_count  = unpack_32_le(buf+0);
+		heritage_offset = unpack_32_le(buf+4);
+
+		if (heritage_count == 0)
+			return -1;
+		if (fseek(pkg->priv->f, heritage_offset, SEEK_SET) != 0)
+			return -1;
+	}
+
+	rc = fread(pkg->guid, 1, 16, pkg->priv->f);
+	if (rc < 16)
+		return -1;
+
+	return 0;
+}
+
 static int pkg_init_names(struct upkg *pkg)
 {
 	size_t rc, len, nbuf = 0;
@@ -212,11 +242,11 @@ static int pkg_init_exports(struct upkg *pkg)
 		}
 
 		len = 0;
-		rc = decode_index(&export->class, buf+len, nbuf-len);
+		rc = upkg_decode_index(&export->class, buf+len, nbuf-len);
 		if (rc == 0) goto err;
 		len += rc;
 
-		rc = decode_index(&export->super, buf+len, nbuf-len);
+		rc = upkg_decode_index(&export->super, buf+len, nbuf-len);
 		if (rc == 0) goto err;
 		len += rc;
 
@@ -224,7 +254,7 @@ static int pkg_init_exports(struct upkg *pkg)
 		export->package = unpack_32_le(buf+len);
 		len += 4;
 
-		rc = decode_index(&tmp, buf+len, nbuf-len);
+		rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
 		if (rc == 0 || tmp < 0 || tmp >= pkg->name_count) goto err;
 		export->name = pkg->priv->names[tmp].name;
 		len += rc;
@@ -233,12 +263,12 @@ static int pkg_init_exports(struct upkg *pkg)
 		export->flags = unpack_32_le(buf+len);
 		len += 4;
 
-		rc = decode_index(&export->size, buf+len, nbuf-len);
+		rc = upkg_decode_index(&export->size, buf+len, nbuf-len);
 		if (rc == 0) goto err;
 		len += rc;
 
 		if (export->size) {
-			rc = decode_index(&export->offset, buf+len, nbuf-len);
+			rc = upkg_decode_index(&export->offset, buf+len, nbuf-len);
 			if (rc == 0) goto err;
 			len += rc;
 		}
@@ -280,12 +310,12 @@ static int pkg_init_imports(struct upkg *pkg)
 		}
 
 		len = 0;
-		rc = decode_index(&tmp, buf+len, nbuf-len);
+		rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
 		if (rc == 0 || len < 0 || len >= pkg->name_count) goto err;
 		import->class_package = pkg->priv->names[tmp].name;
 		len += rc;
 
-		rc = decode_index(&tmp, buf+len, nbuf-len);
+		rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
 		if (rc == 0 || len < 0 || len >= pkg->name_count) goto err;
 		import->class_name = pkg->priv->names[tmp].name;
 		len += rc;
@@ -294,7 +324,7 @@ static int pkg_init_imports(struct upkg *pkg)
 		import->package = unpack_32_le(buf+len);
 		len += 4;
 
-		rc = decode_index(&tmp, buf+len, nbuf-len);
+		rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
 		if (rc == 0 || len < 0 || len >= pkg->name_count) goto err;
 		import->object_name = pkg->priv->names[tmp].name;
 		len += rc;
@@ -333,6 +363,10 @@ struct upkg *upkg_fopen(const char *path)
 	}
 	pkg->priv->f = f;
 
+	if (pkg_init_guid(pkg) != 0) {
+		goto err2;
+	}
+
 	if (pkg_init_names(pkg) != 0) {
 		goto err2;
 	}
@@ -385,3 +419,81 @@ const char *upkg_get_name(struct upkg *pkg, unsigned long idx)
 		return 0;
 	return pkg->priv->names[idx].name;
 }
+
+struct upkg_file *upkg_export_open(struct upkg *pkg, unsigned long idx)
+{
+	struct upkg_file *f;
+
+	if (idx >= pkg->export_count)
+		return NULL;
+
+	f = malloc(sizeof *f);
+	if (f == NULL)
+		return NULL;
+
+	*f = (struct upkg_file) {
+		.pkg  = pkg,
+		.base = pkg->priv->exports[idx].offset,
+		.len  = pkg->priv->exports[idx].size,
+		.name = pkg->priv->exports[idx].name,
+	};
+
+	return f;
+}
+
+void upkg_export_close(struct upkg_file *f)
+{
+	if (f->pkg->priv->last_file == f)
+		f->pkg->priv->last_file = NULL;
+	free(f);
+}
+
+long upkg_export_tell(struct upkg_file *f)
+{
+	return f->offset;
+}
+
+int upkg_export_seek(struct upkg_file *f, long offset, int whence)
+{
+	int rc = EOF;
+
+	switch (whence) {
+	case SEEK_CUR:
+		offset = f->offset + offset;
+	case SEEK_SET:
+		if (offset < 0 || offset > f->len)
+			return EOF;
+		rc = fseek(f->pkg->priv->f, f->base + offset, SEEK_SET);
+		break;
+	case SEEK_END:
+		offset = -offset;
+		if (offset < 0 || offset > f->len)
+			return EOF;
+		offset = f->len - offset;
+		rc = fseek(f->pkg->priv->f, f->base + offset, SEEK_SET);
+		break;
+	}
+
+	if (rc == 0)
+		f->pkg->priv->last_file = f;
+	return rc;
+}
+
+size_t upkg_export_read(struct upkg_file *f, void *buf, size_t n)
+{
+	size_t want = MIN(n, f->len - f->offset);
+	size_t rc;
+
+	if (want == 0) {
+		return 0;
+	}
+
+	if (f != f->pkg->priv->last_file) {
+		if (fseek(f->pkg->priv->f, f->base + f->offset, SEEK_SET))
+			return 0;
+	}
+
+	rc = fread(buf, 1, want, f->pkg->priv->f);
+	f->offset += rc;
+	return rc;
+}