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#include <elf.h>
#include <merror.h>
#include <stdio.h>
#include <stdlib.h>
#include <melf.h>
#include "link.h"
#define SYMTAB_INIT_LEN 8
int symtab_init(struct symbol_table *symtab)
{
symtab->len = 1;
symtab->size = SYMTAB_INIT_LEN;
symtab->syms = malloc(sizeof(Elf32_Sym) * SYMTAB_INIT_LEN);
if (symtab->syms == NULL) {
PERROR("cannot alloc");
return M_ERROR;
}
symtab->syms[0] = (Elf32_Sym){0};
symtab->map = NULL;
return M_SUCCESS;
}
void symtab_free(struct symbol_table *symtab)
{
free(symtab->syms);
}
int symtab_push(struct symbol_table *symtab, const Elf32_Sym *sym)
{
if (symtab->len >= symtab->size) {
size_t size = symtab->size *= 2;
void *new = realloc(symtab->syms, sizeof(Elf32_Sym) * size);
if (new == NULL) {
PERROR("cannot realloc");
return M_ERROR;
}
symtab->size = size;
symtab->syms = new;
}
symtab->syms[symtab->len++] = *sym;
return M_SUCCESS;
}
int symtab_get(struct symbol_table *symtab, Elf32_Sym **res, const char *name,
int32_t obj_idx)
{
for (size_t i = 1; i < symtab->len; i++) {
Elf32_Sym *sym = &symtab->syms[i];
const char *symname = symtab->strtab->data + B32(sym->st_name);
if (strcmp(name, symname) != 0)
continue;
// ignore absolute symbols
if (B16(sym->st_shndx) == SHN_ABS)
continue;
// only allow retrevial of local variables from the
// same object
if (sym->st_info >> 4 != STB_GLOBAL && symtab->map != NULL &&
obj_idx >= 0) {
// we need to change the index by one since
// symbol tables always start will a NULl symbol
struct object *obj = symtab->map->meta[i - 1];
if (obj->index != (uint32_t)obj_idx)
continue;
} else if (obj_idx < 0 && sym->st_info >> 4 != STB_GLOBAL) {
// when obj_idx is -1, we only want to reutrn
// global symbols
continue;
}
if (res != NULL)
*res = sym;
return M_SUCCESS;
}
return M_ERROR;
}
int symtab_map_push(struct symbol_table_mapping *symtabm, struct object *meta)
{
if (symtabm->len >= symtabm->size) {
uint32_t size = symtabm->size * 2;
void *new = realloc(symtabm->meta,
sizeof(struct object *) * size);
if (new == NULL) {
PERROR("cannot realloc");
return M_ERROR;
}
symtabm->size = size;
symtabm->meta = new;
}
symtabm->meta[symtabm->len++] = meta;
return M_SUCCESS;
}
int symtab_map_init(struct symbol_table_mapping *symtabm)
{
symtabm->len = 0;
symtabm->size = SYMTAB_INIT_LEN;
symtabm->meta = malloc(sizeof(struct object *) * symtabm->size);
if (symtabm->meta == NULL) {
PERROR("cannot alloc");
return M_ERROR;
}
return M_SUCCESS;
}
void symtab_map_free(struct symbol_table_mapping *symtabm)
{
free(symtabm->meta);
}
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