From 05e3500b16aa61732a22ffafe1b3edb3933d1897 Mon Sep 17 00:00:00 2001
From: Nick Bowler <nbowler@draconx.ca>
Date: Fri, 5 Jun 2009 21:20:50 -0400
Subject: [PATCH] Implement import table parsing.

---
 libupkg.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++++-----
 upkg.c    |  1 +
 2 files changed, 83 insertions(+), 7 deletions(-)

diff --git a/libupkg.c b/libupkg.c
index a269698..85767a2 100644
--- a/libupkg.c
+++ b/libupkg.c
@@ -13,16 +13,24 @@ struct upkg_name {
 };
 
 struct upkg_export {
-	long class, super, name;
-	unsigned long package, flags;
+	const char *name;
+
+	long package, class, super;
+	unsigned long flags;
 	unsigned long size, offset;
 };
 
+struct upkg_import {
+	const char *class_package, *class_name, *object_name;
+	long package;
+};
+
 struct upkg_private {
 	FILE *f;
 
 	struct upkg_name   *names;
 	struct upkg_export *exports;
+	struct upkg_import *imports;
 
 	unsigned long name_offset, export_offset, import_offset;
 	unsigned char guid[16];
@@ -159,6 +167,7 @@ static int pkg_init_exports(struct upkg *pkg)
 
 	while (index < pkg->export_count) {
 		struct upkg_export *export = &pkg->priv->exports[index];
+		long tmp;
 
 		/* Read some data into buffer. */
 		if (!feof(pkg->priv->f)) {
@@ -181,8 +190,9 @@ static int pkg_init_exports(struct upkg *pkg)
 		export->package = unpack_32_le(buf+len);
 		len += 4;
 
-		rc = decode_index(&export->name, buf+len, nbuf-len);
-		if (rc == 0) goto err;
+		rc = 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;
 
 		if (nbuf-len < 4) goto err;
@@ -210,6 +220,62 @@ err:
 	return -1;
 }
 
+static int pkg_init_imports(struct upkg *pkg)
+{
+	size_t rc, len, nbuf = 0;
+	unsigned long index = 0;
+	char buf[512];
+
+	if (fseek(pkg->priv->f, pkg->priv->import_offset, SEEK_SET) != 0)
+		return -1;
+
+	pkg->priv->imports = malloc(pkg->import_count * sizeof *pkg->priv->imports);
+	if (!pkg->priv->imports)
+		return -1;
+
+	while (index < pkg->import_count) {
+		struct upkg_import *import = &pkg->priv->imports[index];
+		long tmp;
+
+		/* Read some data into buffer. */
+		if (!feof(pkg->priv->f)) {
+			rc = fread(buf+nbuf, 1, sizeof buf-nbuf, pkg->priv->f);
+			if (rc == 0)
+				goto err;
+			nbuf += rc;
+		}
+
+		len = 0;
+		rc = 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);
+		if (rc == 0 || len < 0 || len >= pkg->name_count) goto err;
+		import->class_name = pkg->priv->names[tmp].name;
+		len += rc;
+
+		if (nbuf-len < 4) goto err;
+		import->package = unpack_32_le(buf+len);
+		len += 4;
+
+		rc = 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;
+
+		nbuf -= len;
+		memmove(buf, buf+len, nbuf);
+		index++;
+	}
+
+	return 0;
+err:
+	free(pkg->priv->imports);
+	return -1;
+}
+
 struct upkg *upkg_fopen(const char *path)
 {
 	unsigned char hdr_buf[UPKG_HDR_SIZE];
@@ -233,17 +299,25 @@ struct upkg *upkg_fopen(const char *path)
 	}
 	pkg->priv->f = f;
 
-	if (pkg_init_exports(pkg) != 0) {
+	if (pkg_init_names(pkg) != 0) {
 		goto err2;
 	}
 
-	if (pkg_init_names(pkg) != 0) {
+	if (pkg_init_exports(pkg) != 0) {
 		goto err3;
 	}
 
+	if (pkg_init_imports(pkg) != 0) {
+		goto err4;
+	}
+
 	return pkg;
-err3:
+err4:
 	free(pkg->priv->exports);
+err3:
+	for (unsigned i = 0; i < pkg->name_count; i++)
+		free(pkg->priv->names[i].name);
+	free(pkg->priv->names);
 err2:
 	free(pkg->priv);
 	free(pkg);
@@ -264,6 +338,7 @@ int upkg_close(struct upkg *pkg)
 		}
 	}
 
+	free(pkg->priv->imports);
 	free(pkg->priv->exports);
 	free(pkg->priv->names);
 	free(pkg->priv);
diff --git a/upkg.c b/upkg.c
index 2694f5b..660819c 100644
--- a/upkg.c
+++ b/upkg.c
@@ -46,6 +46,7 @@ int main(int argc, char **argv)
 	}
 
 	printf("Exports: %lu\n", pkg->export_count);
+	printf("Imports: %lu\n", pkg->import_count);
 
 	upkg_close(pkg);
 	return 0;
-- 
2.43.2