libupkg: Add signed integer unpacking to fix incorrect signedness issue.

[upkg.git] / src / libupkg.c

diff --git a/src/libupkg.c b/src/libupkg.c
index f7c55ba2fbf26428c110369e021d7c4d0bb6484e..3f07095b4f29c2847e995e6d4bb8a012185992af 100644 (file)
--- a/src/libupkg.c
+++ b/src/libupkg.c
@@ -124,11 +124,39 @@ 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;
        unsigned long index = 0;
-       char buf[512];
+       unsigned char buf[512];
 
        if (fseek(pkg->priv->f, pkg->priv->name_offset, SEEK_SET) != 0)
                return -1;
@@ -163,7 +191,7 @@ static int pkg_init_names(struct upkg *pkg)
                        memmove(buf, buf+len+1, nbuf);
                        index++;
                } else {
-                       char *c = memchr(buf, 0, nbuf);
+                       unsigned char *c = memchr(buf, 0, nbuf);
                        if (!c || nbuf <= c - buf + 5)
                                goto err;
                        len = c - buf + 1;
@@ -192,7 +220,7 @@ static int pkg_init_exports(struct upkg *pkg)
 {
        size_t rc, len, nbuf = 0;
        unsigned long index = 0;
-       char buf[512];
+       unsigned char buf[512];
 
        if (fseek(pkg->priv->f, pkg->priv->export_offset, SEEK_SET) != 0)
                return -1;
@@ -223,7 +251,7 @@ static int pkg_init_exports(struct upkg *pkg)
                len += rc;
 
                if (nbuf-len < 4) goto err;
-               export->package = unpack_32_le(buf+len);
+               export->package = unpack_s32_le(buf+len);
                len += 4;
 
                rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
@@ -235,13 +263,15 @@ static int pkg_init_exports(struct upkg *pkg)
                export->flags = unpack_32_le(buf+len);
                len += 4;
 
-               rc = upkg_decode_index(&export->size, buf+len, nbuf-len);
-               if (rc == 0) goto err;
+               rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
+               if (rc == 0 || tmp < 0) goto err;
+               export->size = tmp;
                len += rc;
 
                if (export->size) {
-                       rc = upkg_decode_index(&export->offset, buf+len, nbuf-len);
-                       if (rc == 0) goto err;
+                       rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
+                       if (rc == 0 || tmp < 0) goto err;
+                       export->offset = tmp;
                        len += rc;
                }
 
@@ -260,7 +290,7 @@ static int pkg_init_imports(struct upkg *pkg)
 {
        size_t rc, len, nbuf = 0;
        unsigned long index = 0;
-       char buf[512];
+       unsigned char buf[512];
 
        if (fseek(pkg->priv->f, pkg->priv->import_offset, SEEK_SET) != 0)
                return -1;
@@ -293,7 +323,7 @@ static int pkg_init_imports(struct upkg *pkg)
                len += rc;
 
                if (nbuf-len < 4) goto err;
-               import->package = unpack_32_le(buf+len);
+               import->package = unpack_s32_le(buf+len);
                len += 4;
 
                rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
@@ -335,6 +365,10 @@ 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;
        }
@@ -388,6 +422,84 @@ const char *upkg_get_name(struct upkg *pkg, unsigned long idx)
        return pkg->priv->names[idx].name;
 }
 
+long upkg_export_find(struct upkg *pkg, const char *name)
+{
+       /* This is wrong.
+        * Export names are not necessarily unique within a package. */
+       for (unsigned i = 0; i < pkg->export_count; i++) {
+               struct upkg_export *export = &pkg->priv->exports[i];
+               if (strcmp(export->name, name) == 0) {
+                       return i;
+               }
+       }
+
+       return -1;
+}
+
+const char *upkg_export_name(struct upkg *pkg, unsigned long idx)
+{
+       if (idx < pkg->export_count)
+               return pkg->priv->exports[idx].name;
+       return NULL;
+}
+
+const char *upkg_export_class(struct upkg *pkg, unsigned long idx,
+                              const char **package)
+{
+       struct upkg_export *export;
+       struct upkg_import *iclass, *ipackage;
+       unsigned long pkg_idx;
+
+       if (idx >= pkg->export_count)
+               return NULL;
+       
+       export = &pkg->priv->exports[idx];
+
+       /* ASSUMPTION: class references are always imports */
+       if (export->class > 0) {
+               fprintf(stderr, "Assumption Violated: class not import\n");
+               return NULL;
+       }
+
+       /* Get the class. */
+       if (export->class == 0) {
+               if (package) *package = "Core";
+               return "Class";
+       }
+
+       pkg_idx = -(export->class + 1);
+       if (pkg_idx >= pkg->import_count)
+               return NULL;
+       iclass = &pkg->priv->imports[pkg_idx];
+
+       /* ASSUMPTION: Class references are always Core.Class */
+       if (strcmp(iclass->class_name, "Class") || strcmp(iclass->class_package, "Core")) {
+               fprintf(stderr, "Assumption Violated: class not Core.Class\n");
+               return NULL;
+       }
+
+       /* ASSUMPTION: Package references are always imports */
+       if (iclass->package >= 0) {
+               fprintf(stderr, "Assumption Violated: package not import\n");
+               return NULL;
+       }
+
+       /* Get the package. */
+       pkg_idx = -(iclass->package + 1);
+       if (pkg_idx >= pkg->import_count)
+               return NULL;
+       ipackage = &pkg->priv->imports[pkg_idx];
+
+       /* ASSUMPTION: Package references are always Core.Package */
+       if (strcmp(ipackage->class_name, "Package") || strcmp(ipackage->class_package, "Core")) {
+               fprintf(stderr, "Assumption Violated: package not Core.Package\n");
+               return NULL;
+       }
+
+       if (package) *package = ipackage->object_name;
+       return iclass->object_name;
+}
+
 struct upkg_file *upkg_export_open(struct upkg *pkg, unsigned long idx)
 {
        struct upkg_file *f;
@@ -442,8 +554,14 @@ int upkg_export_seek(struct upkg_file *f, long offset, int whence)
                break;
        }
 
-       if (rc == 0)
+       if (rc == 0) {
                f->pkg->priv->last_file = f;
+               f->offset = offset;
+               f->eof = 0;
+       } else if (f->pkg->priv->last_file == f) {
+               f->pkg->priv->last_file = NULL;
+       }
+
        return rc;
 }
 
@@ -463,5 +581,8 @@ size_t upkg_export_read(struct upkg_file *f, void *buf, size_t n)
 
        rc = fread(buf, 1, want, f->pkg->priv->f);
        f->offset += rc;
+
+       if (want < n || (rc < want && feof(f->pkg->priv->f)))
+               f->eof = 1;
        return rc;
 }