nooc

commit e5868e1b7a0412cc31a0bca2ab8801af3a6f494d
parent cbcd41da9f384500dc4eb6ad0b7e2a0dd41c3c8e
Author: Nihal Jere <nihal@nihaljere.xyz>
Date:   Fri, 19 Nov 2021 10:14:15 -0600

extract elf

Diffstat:
M
Makefile
 | 
4
++--
A
elf.c
 | 
67
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
A
elf.h
 | 
1
+
M
main.c
 | 
62
+-------------------------------------------------------------

4 files changed, 71 insertions(+), 63 deletions(-)
diff --git a/Makefile b/Makefile
@@ -1,5 +1,5 @@
 .c.o:
 	$(CC) -c $< -o $@
 
-nooc: main.o array.o util.o x64.o
-	$(CC) main.o array.o x64.o util.o -o nooc
+nooc: main.o array.o util.o x64.o elf.o
+	$(CC) main.o array.o x64.o util.o elf.o -o nooc
diff --git a/elf.c b/elf.c
@@ -0,0 +1,67 @@
+#include <elf.h>
+#include <stdio.h>
+
+#include "nooc.h"
+#include "elf.h"
+
+int
+elf(char *text, size_t len, char* data, size_t dlen, FILE *f)
+{
+	Elf64_Ehdr ehdr = { 0 };
+	Elf64_Phdr phdr_text = { 0 };
+	Elf64_Phdr phdr_data = { 0 };
+
+	ehdr.e_ident[0] = ELFMAG0;
+	ehdr.e_ident[1] = ELFMAG1;
+	ehdr.e_ident[2] = ELFMAG2;
+	ehdr.e_ident[3] = ELFMAG3;
+	ehdr.e_ident[4] = ELFCLASS64;
+	ehdr.e_ident[5] = ELFDATA2LSB;
+	ehdr.e_ident[6] = EV_CURRENT;
+	ehdr.e_ident[7] = ELFOSABI_LINUX;
+
+	ehdr.e_type = ET_EXEC;
+	ehdr.e_machine = EM_X86_64;
+	ehdr.e_version = EV_CURRENT;
+
+	ehdr.e_entry = 0x1000;
+	ehdr.e_phoff = sizeof(ehdr);
+	ehdr.e_phentsize = sizeof(phdr_text);
+	ehdr.e_phnum = 2;
+
+	ehdr.e_ehsize = sizeof(ehdr);
+
+	size_t pretextlen = sizeof(ehdr) + sizeof(phdr_text) + sizeof(phdr_data);
+
+	phdr_text.p_type = PT_LOAD;
+	phdr_text.p_offset = 0x1000;
+	phdr_text.p_vaddr = 0x1000;
+	phdr_text.p_paddr = 0x1000;
+	phdr_text.p_filesz = len;
+	phdr_text.p_memsz = len;
+	phdr_text.p_flags = PF_R | PF_X;
+	phdr_text.p_align = 0x1000;
+
+	phdr_data.p_type = PT_LOAD;
+	phdr_data.p_offset = DATA_OFFSET;
+	phdr_data.p_vaddr = DATA_OFFSET;
+	phdr_data.p_paddr = DATA_OFFSET;
+	phdr_data.p_filesz = dlen;
+	phdr_data.p_memsz = dlen;
+	phdr_data.p_flags = PF_R;
+	phdr_data.p_align = 0x1000;
+
+	fwrite(&ehdr, 1, sizeof(Elf64_Ehdr), f);
+	fwrite(&phdr_text, sizeof(phdr_text), 1, f);
+	fwrite(&phdr_data, sizeof(phdr_data), 1, f);
+	char empty = 0;
+
+	for (int i = 0; i < 0x1000 - pretextlen; i++) {
+		fwrite(&empty, 1, 1, f);
+	}
+	fwrite(text, 1, len, f);
+	for (int i = 0; i < 0x1000 - len; i++) {
+		fwrite(&empty, 1, 1, f);
+	}
+	fwrite(data, 1, dlen, f);
+}
diff --git a/elf.h b/elf.h
@@ -0,0 +1 @@
+int elf(char *text, size_t len, char* data, size_t dlen, FILE *f);
diff --git a/main.c b/main.c
@@ -13,68 +13,8 @@
 #include "x64.h"
 #include "util.h"
 #include "nooc.h"
+#include "elf.h"
 
-int
-elf(char *text, size_t len, char* data, size_t dlen, FILE *f)
-{
-	Elf64_Ehdr ehdr = { 0 };
-	Elf64_Phdr phdr_text = { 0 };
-	Elf64_Phdr phdr_data = { 0 };
-
-	ehdr.e_ident[0] = ELFMAG0;
-	ehdr.e_ident[1] = ELFMAG1;
-	ehdr.e_ident[2] = ELFMAG2;
-	ehdr.e_ident[3] = ELFMAG3;
-	ehdr.e_ident[4] = ELFCLASS64;
-	ehdr.e_ident[5] = ELFDATA2LSB;
-	ehdr.e_ident[6] = EV_CURRENT;
-	ehdr.e_ident[7] = ELFOSABI_LINUX;
-
-	ehdr.e_type = ET_EXEC;
-	ehdr.e_machine = EM_X86_64;
-	ehdr.e_version = EV_CURRENT;
-
-	ehdr.e_entry = 0x1000;
-	ehdr.e_phoff = sizeof(ehdr);
-	ehdr.e_phentsize = sizeof(phdr_text);
-	ehdr.e_phnum = 2;
-
-	ehdr.e_ehsize = sizeof(ehdr);
-
-	size_t pretextlen = sizeof(ehdr) + sizeof(phdr_text) + sizeof(phdr_data);
-
-	phdr_text.p_type = PT_LOAD;
-	phdr_text.p_offset = 0x1000;
-	phdr_text.p_vaddr = 0x1000;
-	phdr_text.p_paddr = 0x1000;
-	phdr_text.p_filesz = len;
-	phdr_text.p_memsz = len;
-	phdr_text.p_flags = PF_R | PF_X;
-	phdr_text.p_align = 0x1000;
-
-	phdr_data.p_type = PT_LOAD;
-	phdr_data.p_offset = DATA_OFFSET;
-	phdr_data.p_vaddr = DATA_OFFSET;
-	phdr_data.p_paddr = DATA_OFFSET;
-	phdr_data.p_filesz = dlen;
-	phdr_data.p_memsz = dlen;
-	phdr_data.p_flags = PF_R;
-	phdr_data.p_align = 0x1000;
-
-	fwrite(&ehdr, 1, sizeof(Elf64_Ehdr), f);
-	fwrite(&phdr_text, sizeof(phdr_text), 1, f);
-	fwrite(&phdr_data, sizeof(phdr_data), 1, f);
-	char empty = 0;
-
-	for (int i = 0; i < 0x1000 - pretextlen; i++) {
-		fwrite(&empty, 1, 1, f);
-	}
-	fwrite(text, 1, len, f);
-	for (int i = 0; i < 0x1000 - len; i++) {
-		fwrite(&empty, 1, 1, f);
-	}
-	fwrite(data, 1, dlen, f);
-}
 struct decls decls;
 struct exprs exprs;