initial import

git-svn-id: file:///home/notaz/opt/svn/PicoDrive@2 be3aeb3a-fb24-0410-a615-afba39da0efa

cpu/Cyclone/epoc/patchtable_symb.c

@@ -0,0 +1,150 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+typedef struct {
+	unsigned long _dontcare1[4];
+	char signature[4];						// 'EPOC'
+	unsigned long iCpu;						// 0x1000 = X86, 0x2000 = ARM, 0x4000 = M*Core
+	unsigned long iCheckSumCode;			// sum of all 32 bit words in .text
+	unsigned long _dontcare3[5];
+	unsigned long iCodeSize;				// size of code, import address table, constant data and export dir |+30
+	unsigned long _dontcare4[12];
+	unsigned long iCodeOffset;				// file offset to code section    |+64
+	unsigned long _dontcare5[2];
+	unsigned long iCodeRelocOffset;			// relocations for code and const |+70
+	unsigned long iDataRelocOffset;			// relocations for data
+	unsigned long iPriority;		// priority of this process (EPriorityHigh=450)
+} E32ImageHeader;
+
+
+typedef struct {
+	unsigned long iSize;				// size of this relocation section
+	unsigned long iNumberOfRelocs;		// number of relocations in this section
+} E32RelocSection;
+
+
+typedef struct {
+	unsigned long base;
+	unsigned long size;
+} reloc_page_header;
+
+
+// E32Image relocation section consists of a number of pages
+// every page has 8 byte header and a number or 16bit relocation entries
+// entry format:
+// 0x3000 | <12bit_reloc_offset>
+//
+// if we have page_header.base == 0x1000 and a reloc entry 0x3110,
+// it means that 32bit value at offset 0x1110 of .text section
+// is relocatable
+
+int main(int argc, char *argv[])
+{
+	FILE *f = 0;
+	unsigned char pattern[8] = { 0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56 };
+	unsigned char *buff, *p;
+	unsigned long patt_offset; // pattern offset in .text section
+	unsigned long size = 0, i, symbols, insert_pos, *handler;
+	unsigned short reloc_entry;
+	E32ImageHeader  *header;
+	E32RelocSection *reloc_section;
+	reloc_page_header *reloc_page;
+
+	if(argc != 3) {
+		printf("usage: %s <e32_exe> <nsymbols>\n\n", argv[0]);
+		printf("note: this was written to fix a problem caused by as v.2.9-psion-98r2 and shouldn't be used for anything else.\n", argv[0]);
+		return 1;
+	}
+	
+	f = fopen(argv[1], "rb+");
+	if(!f) {
+		printf("%s: couldn't open %s\n", argv[0], argv[1]);
+		return 2;
+	}
+
+	symbols = atoi(argv[2]);
+
+	// read the file
+	fseek(f,0,SEEK_END); size=ftell(f); fseek(f,0,SEEK_SET);
+	buff = (unsigned char *) malloc(size);
+	fread(buff,1,size,f);
+
+	header = (E32ImageHeader *) buff;
+
+	if(strncmp(header->signature, "EPOC", 4) || header->iCpu != 0x2000) {
+		printf("%s: not a E32 executable image for ARM target.\n", argv[0]);
+		fclose(f);
+		free(buff);
+		return 2;
+	}
+
+	// find the pattern
+	for(i = 0; i < size-8; i++)
+		if(memcmp(buff+i, pattern, 8) == 0) break;
+	if(i == size-8 || i < 4) {
+		printf("%s: failed to find the pattern.\n", argv[0]);
+		fclose(f);
+		free(buff);
+		return 3;
+	}
+	patt_offset = i - header->iCodeOffset;
+
+	// find suitable reloc section
+	reloc_section = (E32RelocSection *) (buff + header->iCodeRelocOffset);
+	for(i = 0, p = buff+header->iCodeRelocOffset+8; i < reloc_section->iSize; ) {
+		reloc_page = (reloc_page_header *) p;
+		if(patt_offset - reloc_page->base >= 0 && patt_offset - reloc_page->base < 0x1000 - symbols*4) break;
+		i += reloc_page->size;
+		p += reloc_page->size;
+	}
+
+	if(i >= reloc_section->iSize) {
+		printf("%s: suitable reloc section not found.\n", argv[0]);
+		fclose(f);
+		free(buff);
+		return 4;
+	}
+
+	// now find the insert pos and update everything
+	insert_pos = p + reloc_page->size - buff;
+	reloc_page->size     += symbols*2;
+	reloc_section->iSize += symbols*2;
+	reloc_section->iNumberOfRelocs += symbols;
+	header->iDataRelocOffset += symbols*2; // data reloc section is now also pushed a little
+	header->iPriority = 450; // let's boost our priority :)
+
+	// replace the placeholders themselves
+	handler = (unsigned long *) (buff + patt_offset + header->iCodeOffset - 4);
+	for(i = 1; i <= symbols; i++)
+		*(handler+i) = *handler;
+	
+	// recalculate checksum
+	header->iCheckSumCode = 0;
+	for(i = 0, p = buff+header->iCodeOffset; i < header->iCodeSize; i+=4, p+=4)
+		header->iCheckSumCode += *(unsigned long *) p;
+
+	// check for possible padding
+	if(!*(buff+insert_pos-1)) insert_pos -= 2;
+
+	// write all this joy
+	fseek(f,0,SEEK_SET);
+	fwrite(buff, 1, insert_pos, f);
+
+	// write new reloc entries
+	for(i = 0; i < symbols; i++) {
+		handler++;
+		reloc_entry = ((unsigned char *) handler - buff - reloc_page->base - header->iCodeOffset) | 0x3000;
+		fwrite(&reloc_entry, 1, 2, f);
+	}
+
+	// write the remaining data
+	fwrite(buff+insert_pos, 1, size-insert_pos, f);
+
+	// done at last!
+	fclose(f);
+	free(buff);
+
+	return 0;
+}