feat: check ident

Makefile

@@ -3,6 +3,7 @@ NAME = ft_nm
 SRC_FILES = main.c \
 			error.c \
 			header.c \
+			ident.c \
 
 INC_FILES = ft_nm.h \
 

inc/ft_nm.h

@@ -14,5 +14,7 @@
 
 void ft_nm_error(const char *path);
 int check_header(Elf64_Ehdr *header);
+int check_ident(unsigned char ident[EI_NIDENT]);
 
 #endif
+

src/error.c

@@ -1,6 +1,4 @@
 #include "ft_nm.h"
-// XXX
-#include <string.h>
 
 void ft_nm_error(const char *path) {
 	char *str = malloc(8 + ft_strlen(path));
@@ -9,3 +7,4 @@ void ft_nm_error(const char *path) {
 	perror(str);
 	free(str);
 }
+

src/header.c

@@ -1,26 +1,7 @@
 #include "ft_nm.h"
 
-int check_magic_number(Elf64_Ehdr *header) {
-	if (ft_strncmp((void *)&header->e_ident[EI_MAG0], "\x7f""ELF", 4)) {
-		return FT_NM_FAILURE;
-	}
-	return FT_NM_SUCCESS;
-}
-
-int check_format(Elf64_Ehdr *header) {
-	if (header->e_ident[EI_CLASS] == ELFCLASSNONE) {
-		printf("problem\n");
-		return FT_NM_FAILURE;
-	}
-	return FT_NM_SUCCESS;
-}
-
 int check_header(Elf64_Ehdr *header) {
-	if (check_magic_number(header) == FT_NM_FAILURE) {
-		return FT_NM_FAILURE;
-	}
-	if (check_format(header) == FT_NM_FAILURE) {
-		return FT_NM_FAILURE;
-	}
+	(void)header;
 	return FT_NM_SUCCESS;
 }
+

src/ident.c

@@ -0,0 +1,47 @@
+#include "ft_nm.h"
+
+int check_magic_number(const char *magic_number) {
+	if (ft_strncmp(magic_number, "\x7f""ELF", 4)) {
+		return FT_NM_FAILURE;
+	}
+	return FT_NM_SUCCESS;
+}
+
+int check_arch(unsigned char arch) {
+	if (arch != ELFCLASS64 && arch != ELFCLASS32) {
+		return FT_NM_FAILURE;
+	}
+	return FT_NM_SUCCESS;
+}
+
+int check_data_format(unsigned char data_format) {
+	if (data_format != ELFDATA2MSB && data_format != ELFDATA2LSB) {
+		return FT_NM_FAILURE;
+	}
+	return FT_NM_SUCCESS;
+}
+
+int check_version(unsigned char version) {
+	if (version != EV_CURRENT) {
+		return FT_NM_FAILURE;
+	}
+	return FT_NM_SUCCESS;
+}
+
+int check_ident(unsigned char ident[EI_NIDENT]) {
+	if (check_magic_number((const char *)&ident[EI_MAG0])
+			== FT_NM_FAILURE) {
+		return FT_NM_FAILURE;
+	}
+	if (check_arch(ident[EI_CLASS]) == FT_NM_FAILURE) {
+		return FT_NM_FAILURE;
+	}
+	if (check_data_format(ident[EI_DATA]) == FT_NM_FAILURE) {
+		return FT_NM_FAILURE;
+	}
+	if (check_version(ident[EI_VERSION]) == FT_NM_FAILURE) {
+		return FT_NM_FAILURE;
+	}
+	return FT_NM_SUCCESS;
+}
+

src/main.c

@@ -18,19 +18,20 @@ int main(int ac, char **av) {
 		ft_nm_error(path);
 	}
 	void *ptr = NULL;
-	Elf64_Ehdr *header;
-
+//	Elf64_Ehdr *header;
+	unsigned char ident[EI_NIDENT];
 	ptr = mmap(NULL, 64, PROT_READ, MAP_PRIVATE, fd, 0);
 	if (ptr != MAP_FAILED) {
-		header = (Elf64_Ehdr *)ptr;
-		if (check_header(header) == FT_NM_FAILURE) {
+		ft_memcpy(ident, ptr, EI_NIDENT);
+		//header = (Elf64_Ehdr *)ptr;
+		if (check_ident(ident) == FT_NM_FAILURE) {
 			printf("ft_nm: %s: file format not recognized\n", path);
 			exit (1);
 		}
-		for (int i = 0; i < 64; i++) {
+		for (int i = 0; i < 16; i++) {
 			print_bits(((char *)ptr)[i]);
 		}
-		if (header->e_ident[EI_OSABI] == 0x00) {
+/*		if (header->e_ident[EI_OSABI] == 0x00) {
 			printf("This ELF is for System V! :)\n");
 		}
 		else if (header->e_ident[EI_OSABI] == 0x03) {
@@ -38,7 +39,9 @@ int main(int ac, char **av) {
 		} else {
 			printf("What's my purpose :(\n");
 		}
+		*/
 	}
 
 	return 0;
 }
+