gdb: send memory map XML to GDB to enforce hw-breakpoints

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redoste 2023-05-25 22:16:58 +02:00
parent 2f6ee59d43
commit eca05ec64c
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@ -161,17 +161,62 @@ static void gdb_send_stop_reply(void)
gdb_send_packet("S05", 3); // SIGTRAP
}
static void gdb_handle_qXfer_packet(const char* packet, const char* data, size_t data_size)
{
char offset_hex[16] = {0}, length_hex[16] = {0};
for (size_t i = 0; i < sizeof(offset_hex); i++) {
offset_hex[i] = *(packet++); // consume offset
if (*packet == ',') break;
}
packet++; // consume ','
for (size_t i = 0; i < sizeof(length_hex); i++) {
length_hex[i] = *(packet++); // consume length
if (*packet == '\0') break;
}
size_t offset = (size_t)gdb_unhexlify(offset_hex);
size_t length = (size_t)gdb_unhexlify(length_hex);
if (offset >= data_size) {
gdb_send_packet("l", 1);
} else if (offset + length >= data_size) {
char *reply_buffer = malloc(data_size - offset + 1);
reply_buffer[0] = 'l';
memcpy(&reply_buffer[1], &data[offset], data_size - offset);
gdb_send_packet(reply_buffer, data_size - offset + 1);
free(reply_buffer);
} else {
char *reply_buffer = malloc(length + 1);
reply_buffer[0] = 'm';
memcpy(&reply_buffer[1], &data[offset], length);
gdb_send_packet(reply_buffer, length + 1);
free(reply_buffer);
}
}
/* We implement the memory-map qXfer extension to mark add-in memory as read-only
* and enforce hardware breakpoints.
* See : https://sourceware.org/gdb/onlinedocs/gdb/Memory-Map-Format.html
* https://sourceware.org/gdb/onlinedocs/gdb/Set-Breaks.html
*/
// TODO : Should we mark other regions as ROM ?
static const char gdb_memory_map_xml[] = "<?xml version=\"1.0\"?>"
"<!DOCTYPE memory-map PUBLIC \"+//IDN gnu.org//DTD GDB Memory Map V1.0//EN\" \"http://sourceware.org/gdb/gdb-memory-map.dtd\">"
"<memory-map>"
"<memory type=\"rom\" start=\"0x00300000\" length=\"0x00200000\"/>" // add-in rom
"<memory type=\"ram\" start=\"0x08101400\" length=\"0x0007ac00\"/>" // add-in ram
"<memory type=\"ram\" start=\"0x8c000000\" length=\"0x01000000\"/>" // fx-CG50 stack
"<memory type=\"ram\" start=\"0x88000000\" length=\"0x01000000\"/>" // Prizm stack
"</memory-map>";
static void gdb_handle_query_packet(const char* packet)
{
if (strncmp("qSupported", packet, 10) == 0) {
const char* qsupported_ans = "PacketSize=255;qXfer:memory-map:read";
const char* qsupported_ans = "PacketSize=255;qXfer:memory-map:read+";
gdb_send_packet(qsupported_ans, strlen(qsupported_ans));
} else if (strncmp("qXfer:memory-map:read::", packet, 23) == 0) {
/* TODO : Implement qXfer and memory map XML
* https://sourceware.org/gdb/onlinedocs/gdb/Memory-Map-Format.html#Memory-Map-Format
* Required for enforcing hbreak : https://sourceware.org/gdb/onlinedocs/gdb/Set-Breaks.html
*/
gdb_send_packet(NULL, 0);
// -1 to not send the NULL terminator
gdb_handle_qXfer_packet(&packet[23], gdb_memory_map_xml, sizeof(gdb_memory_map_xml) - 1);
} else {
gdb_send_packet(NULL, 0);
}