view leo-obj/tool/tables.c @ 392:35009c936a4a

compal/melody-extr: first attempt at actual melody extraction
author Mychaela Falconia <falcon@freecalypso.org>
date Fri, 01 Apr 2022 06:03:47 +0000
parents fd772de226cb
children
line wrap: on
line source

/*
 * This C module will contain functions for the initial parsing
 * of the section and symbol tables.
 */

#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include "filestruct.h"
#include "intstruct.h"
#include "globals.h"

extern unsigned get_u16(), get_u32();

static char *
get_secorsym_name(ptr)
	u_char *ptr;
{
	char *alloc;

	if (ptr[0]) {
		if (ptr[7]) {
			alloc = malloc(9);
			if (!alloc) {
				perror("malloc");
				exit(1);
			}
			bcopy(ptr, alloc, 8);
			alloc[8] = '\0';
			return(alloc);
		} else
			return((char *) ptr);
	}
	if (ptr[1] || ptr[2] || ptr[3]) {
		fprintf(stderr, "error: malformed name in %s at offset 0x%x\n",
			objfilename, ptr - filemap);
		exit(1);
	}
	return(filemap + strtab_offset + get_u32(ptr+4));
}

get_int_section_table()
{
	unsigned n;

	sections = malloc(sizeof(struct internal_scnhdr) * nsections);
	if (!sections) {
		perror("malloc");
		exit(1);
	}
	for (n = 0; n < nsections; n++) {
		sections[n].name = get_secorsym_name(sections_raw[n].s_name);
		if (get_u32(sections_raw[n].s_paddr))
			fprintf(stderr,
				"warning: section #%u (%s) has nonzero paddr\n",
				n, sections[n].name);
		if (get_u32(sections_raw[n].s_vaddr))
			fprintf(stderr,
				"warning: section #%u (%s) has nonzero vaddr\n",
				n, sections[n].name);
		sections[n].size = get_u32(sections_raw[n].s_size);
		sections[n].data_offset = get_u32(sections_raw[n].s_scnptr);
		sections[n].reloc_offset = get_u32(sections_raw[n].s_relptr);
		sections[n].line_offset = get_u32(sections_raw[n].s_lnnoptr);
		sections[n].nreloc = get_u32(sections_raw[n].s_nreloc);
		sections[n].nlineent = get_u32(sections_raw[n].s_nlnno);
		sections[n].flags = get_u32(sections_raw[n].s_flags);
		if (get_u16(sections_raw[n].s_reserved))
			fprintf(stderr,
	"warning: section #%u (%s): some nonzero value in s_reserved bytes\n",
				n, sections[n].name);
		if (get_u16(sections_raw[n].s_page))
			fprintf(stderr,
	"warning: section #%u (%s): some nonzero value in s_page bytes\n",
				n, sections[n].name);
		sections[n].nsymbols = 0;
		sections[n].sorted_symbols = 0;
		sections[n].int_relocs = 0;
		if (!strncmp(sections[n].name, ".text", 5))
			sections[n].disasm_mode = DISASM_MODE_CODE;
		else if (!strcmp(sections[n].name, ".const"))
			sections[n].disasm_mode = DISASM_MODE_DATA;
		else if (!strcmp(sections[n].name, ".cinit"))
			sections[n].disasm_mode = DISASM_MODE_DATA;
		else if (!strcmp(sections[n].name, ".data"))
			sections[n].disasm_mode = DISASM_MODE_DATA;
		else if (!strcmp(sections[n].name, ".bss"))
			sections[n].disasm_mode = DISASM_MODE_BSS;
		else
			sections[n].disasm_mode = DISASM_MODE_UNKNOWN;
		sections[n].hints = 0;
	}
}

get_int_symbol_table()
{
	unsigned n;
	struct internal_syment *in;

	symtab = malloc(sizeof(struct internal_syment *) * nsymtab);
	if (!symtab) {
		perror("malloc");
		exit(1);
	}
	for (n = 0; n < nsymtab; ) {
		in = malloc(sizeof(struct internal_syment));
		if (!in) {
			perror("malloc");
			exit(1);
		}
		symtab[n] = in;
		in->number = n;
		in->name = get_secorsym_name(symtab_raw[n].e_name);
		in->value = get_u32(symtab_raw[n].e_value);
		in->scnum = get_s16(symtab_raw[n].e_scnum);
		if (in->scnum > 0) {
			if (in->scnum > nsections) {
				fprintf(stderr,
					"symtab entry #%u: scnum too big\n", n);
				exit(1);
			}
			in->section = sections + in->scnum - 1;
			in->section->nsymbols++;
		} else if (in->scnum < -2) {
			fprintf(stderr,
				"symtab entry #%u: scnum < -2\n", n);
			exit(1);
		} else
			in->section = 0;
		in->type = get_u16(symtab_raw[n].e_type);
		in->class = symtab_raw[n].e_sclass;
		in->struct_name = 0;
		in->struct_name_raw = 0;
		switch (symtab_raw[n++].e_numaux) {
		case 0:
			in->aux = 0;
			continue;
		case 1:
			if (n >= nsymtab) {
				fprintf(stderr,
				"error: last symbol's aux spills over\n");
				exit(1);
			}
			symtab[n] = 0;
			in->aux = (u_char *)(symtab_raw + n);
			n++;
			continue;
		default:
			n--;
			fprintf(stderr, "symtab entry #%u: invalid numaux\n",
				n);
			exit(1);
		}
	}
}