We can now load ELF binaries !!!

3 files changed, 126 insertions, 1 deletions

diff --git a/Source/Kernel/Linker/Binary.proto.cpp b/Source/Kernel/Linker/Binary.proto.cpp
index 6053f22..c0345da 100644
--- a/Source/Kernel/Linker/Binary.proto.cpp
+++ b/Source/Kernel/Linker/Binary.proto.cpp
@@ -1,16 +1,18 @@
 #include "Binary.proto.h"
 
 #include <Linker/MelonBinary.class.h>
+#include <Linker/ElfBinary.class.h>
 
 Binary* (*loaders[])(File& file) = {
 	&MelonBinary::load,
-
+	&ElfBinary::load,
 0 };
 
 Binary* Binary::load(File& file) {
 	Binary* r = 0;
 	u32int i = 0;
 	while (loaders[i] != 0) {
+		file.seek(0, SM_BEGINNING);
 		r = loaders[i](file);	//Call loader
 		if (r != 0) break;
 		i++;
diff --git a/Source/Kernel/Linker/ElfBinary.class.cpp b/Source/Kernel/Linker/ElfBinary.class.cpp
new file mode 100644
index 0000000..450053f
--- /dev/null
+++ b/Source/Kernel/Linker/ElfBinary.class.cpp
@@ -0,0 +1,55 @@
+#include "ElfBinary.class.h"
+#include <TaskManager/Task.ns.h>
+
+ElfBinary::~ElfBinary() {
+	for (SimpleList<phdr_t> *iter = m_phdr; iter != 0; iter = iter->next()) {
+		delete iter->v().data;
+	}
+}
+
+Binary* ElfBinary::load(File& file) {
+	elf_ehdr_t hdr;
+	file.read<elf_ehdr_t> (&hdr);
+	//Verify we have an elf file
+	if (hdr.e_ident[0] != 0x7F or hdr.e_ident[1] != 'E' or hdr.e_ident[2] != 'L' or hdr.e_ident[3] != 'F') return 0;
+
+	//Store elf header into a new ElfBinary
+	ElfBinary* b = new ElfBinary();
+	memcpy((u8int*)&b->m_ehdr, (const u8int*) &hdr, sizeof(elf_ehdr_t));
+	b->m_phdr = 0;
+
+	//Load program headers
+	file.seek(hdr.e_phoff, SM_BEGINNING);
+	for (u32int i = 0; i < hdr.e_phnum; i++) {
+		b->m_phdr = b->m_phdr->cons(phdr_t());
+		file.read<elf_phdr_t>(&b->m_phdr->v().h);	//Load current entry from file
+	}
+	//Load data
+	for (SimpleList<phdr_t> *iter = b->m_phdr; iter != 0; iter = iter->next()) {
+		iter->v().data = (u8int*)Mem::kalloc(iter->v().h.p_filesz);
+		file.seek(iter->v().h.p_offset, SM_BEGINNING);
+		file.read(iter->v().h.p_filesz, iter->v().data);
+	}
+
+	return b;
+}
+
+thread_entry_t ElfBinary::toProcess(Process* p) {
+	for (SimpleList<phdr_t> *iter = m_phdr; iter != 0; iter = iter->next()) {
+		phdr_t &e = iter->v();
+		if (e.h.p_type == PT_LOAD) {
+			for (u32int i = e.h.p_vaddr; i < e.h.p_vaddr + e.h.p_memsz; i += 0x1000) {
+				p->getPagedir()->allocFrame(i, true, true);
+			}
+			p->getPagedir()->switchTo();
+			memcpy((u8int*)e.h.p_vaddr, (const u8int*)e.data, e.h.p_filesz);
+			if (e.h.p_memsz > e.h.p_filesz) {	//set to zero all the remaining space
+				u8int* x = (u8int*)e.h.p_vaddr;
+				for (u32int i = e.h.p_vaddr + e.h.p_filesz; i < e.h.p_filesz; i++) {
+					x[i] = 0;
+				}
+			}
+		}
+	}
+	return (thread_entry_t)m_ehdr.e_entry;
+}
diff --git a/Source/Kernel/Linker/ElfBinary.class.h b/Source/Kernel/Linker/ElfBinary.class.h
new file mode 100644
index 0000000..311e2e6
--- /dev/null
+++ b/Source/Kernel/Linker/ElfBinary.class.h
@@ -0,0 +1,68 @@
+#ifndef DEF_ELFBINARY_CLASS_H
+#define DEF_ELFBINARY_CLASS_H
+
+#include <Linker/Binary.proto.h>
+#include <Library/SimpleList.class.h>
+
+/* p_type */
+#define	PT_NULL             0
+#define	PT_LOAD             1
+#define	PT_DYNAMIC          2
+#define	PT_INTERP           3
+#define	PT_NOTE             4
+#define	PT_SHLIB            5
+#define	PT_PHDR             6
+#define	PT_LOPROC  0x70000000
+#define	PT_HIPROC  0x7fffffff
+
+struct elf_ehdr_t {
+	u8int e_ident[16];      /* ELF identification */
+	u16int e_type;             /* 2 (exec file) */
+	u16int e_machine;          /* 3 (intel architecture) */
+	u32int e_version;          /* 1 */
+	u32int e_entry;            /* starting point */
+	u32int e_phoff;            /* program header table offset */
+	u32int e_shoff;            /* section header table offset */
+	u32int e_flags;            /* various flags */
+	u16int e_ehsize;           /* ELF header (this) size */
+
+	u16int e_phentsize;        /* program header table entry size */
+	u16int e_phnum;            /* number of entries */
+
+	u16int e_shentsize;        /* section header table entry size */
+	u16int e_shnum;            /* number of entries */
+
+	u16int e_shstrndx;         /* index of the section name string table */
+};
+
+struct elf_phdr_t {
+	u32int p_type;             /* type of segment */
+	u32int p_offset;
+	u32int p_vaddr;
+	u32int p_paddr;
+	u32int p_filesz;
+	u32int p_memsz;
+	u32int p_flags;
+	u32int p_align;
+};
+
+struct phdr_t {
+	elf_phdr_t h;
+	u8int* data;
+};
+
+class ElfBinary : public Binary {
+	private:
+	elf_ehdr_t m_ehdr;
+	SimpleList<phdr_t> *m_phdr;
+
+	ElfBinary() {}
+
+	public:
+	virtual ~ElfBinary();
+	static Binary* load(File& file);
+
+	thread_entry_t toProcess(Process* p);
+};
+
+#endif