Replace appimage_get_elf_size implementation by the its C++ version

src/libappimage/libappimage.cpp

@@ -19,4 +19,15 @@ int appimage_get_type(const char* path, bool verbose) {
     }
 }
 
+ssize_t appimage_get_elf_size(const char* fname) {
+    try {
+        AppImage appImage(fname);
+        return appImage.getPayloadOffset();
+    } catch (...) {}
+
+    return 0;
+}
+
+
+
 }

src/libappimage_shared/elf.c

@@ -117,41 +117,7 @@ static off_t read_elf64(FILE* fd)
 	return sht_end > last_section_end ? sht_end : last_section_end;
 }
 
-ssize_t appimage_get_elf_size(const char* fname) {
-    off_t ret;
-    FILE* fd = NULL;
-    off_t size = -1;
-
-	fd = fopen(fname, "rb");
-	if (fd == NULL) {
-		fprintf(stderr, "Cannot open %s: %s\n",
-			fname, strerror(errno));
-		return -1;
-	}
-	ret = fread(ehdr.e_ident, 1, EI_NIDENT, fd);
-	if (ret != EI_NIDENT) {
-		fprintf(stderr, "Read of e_ident from %s failed: %s\n",
-			fname, strerror(errno));
-		return -1;
-	}
-	if ((ehdr.e_ident[EI_DATA] != ELFDATA2LSB) &&
-		(ehdr.e_ident[EI_DATA] != ELFDATA2MSB)) {
-		fprintf(stderr, "Unkown ELF data order %u\n",
-			ehdr.e_ident[EI_DATA]);
-		return -1;
-	}
-	if (ehdr.e_ident[EI_CLASS] == ELFCLASS32) {
-		size = read_elf32(fd);
-	} else if (ehdr.e_ident[EI_CLASS] == ELFCLASS64) {
-		size = read_elf64(fd);
-	} else {
-		fprintf(stderr, "Unknown ELF class %u\n", ehdr.e_ident[EI_CLASS]);
-		return -1;
-	}
 
-	fclose(fd);
-	return size;
-}
 
 /* Return the offset, and the length of an ELF section with a given name in a given ELF file */
 bool appimage_get_elf_section_offset_and_length(const char* fname, const char* section_name, unsigned long* offset, unsigned long* length) {