From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert Picco To: Robert Picco Cc: Andrew Cagney , gdb-patches@sources.redhat.com Subject: Re: new gdb remote packet type Date: Tue, 11 May 2004 17:31:00 -0000 Message-id: <40A10F56.1010807@hp.com> References: <407F2BAB.4060408@hp.com> <40802711.3040104@gnu.org> <4087E8C0.30806@hp.com> <4087EE4B.4010805@gnu.org> <40912015.7070902@hp.com> <40928D64.8010209@gnu.org> <4097D9DE.2030004@hp.com> <40993C21.1040500@gnu.org> <409A95AB.6020101@hp.com> X-SW-Source: 2004-05/msg00339.html Andrew have you had an opportunity to review this? thanks, Bob Robert Picco wrote: Andrew Cagney wrote: Anyway, it sounds like you might (dig dig) be more interested in the attached patch+hack (fernando nasser gets credit for the patch, I deny responsibility for the hack bit :-). It adds a P packet for fetching individual registers which is something the existing remote protocol spec doco hints at. Andrew Seems remote.c currently supports "P" packet for storing a single register would you find a patch supporting the "p" packet for fetching a single register to be acceptable? This would put the minimum payload on the wire and complement the "P" packet. It's similar to the patch (hack) you forwarded but a complete implementation. Bob *** gdb-6.1-orig/gdb/remote.c 2004-02-25 15:41:00.000000000 -0500 --- gdb-6.1/gdb/remote.c 2004-05-06 14:05:47.000000000 -0400 *************** *** 809,814 **** --- 809,831 ---- show_packet_config_cmd (&remote_protocol_E); } + static struct packet_config remote_protocol_p; + + static void + set_remote_protocol_p_packet_cmd (char *args, int from_tty, + struct cmd_list_element *c) + { + update_packet_config (&remote_protocol_p); + } + + static void + show_remote_protocol_p_packet_cmd (char *args, int from_tty, + struct cmd_list_element *c) + { + show_packet_config_cmd (&remote_protocol_p); + } + + /* Should we try the 'P' (set register) request? */ *************** *** 2080,2085 **** --- 2097,2103 ---- update_packet_config (&remote_protocol_e); update_packet_config (&remote_protocol_E); update_packet_config (&remote_protocol_P); + update_packet_config (&remote_protocol_p); update_packet_config (&remote_protocol_qSymbol); update_packet_config (&remote_protocol_vcont); for (i = 0; i < NR_Z_PACKET_TYPES; i++) *************** *** 3240,3245 **** --- 3258,3293 ---- /* Read the remote registers into the block REGS. */ /* Currently we just read all the registers, so we don't use regnum. */ + static int + fetch_register_using_p (int regnum) + { + struct remote_state *rs = get_remote_state (); + char *buf = alloca (rs->remote_packet_size), *p; + char regp[MAX_REGISTER_SIZE]; + int i; + + buf[0] = 'p'; + bin2hex((char *) ®num, &buf[1], sizeof(regnum)); + buf[9] = 0; + remote_send (buf, rs->remote_packet_size); + if (buf[0] != 0 && buf[0] != 'E') { + p = buf; + i = 0; + while (p[0] != 0) { + if (p[1] == 0) { + error("fetch_register_using_p: early buf termination"); + return 0; + } + regp[i++] = fromhex (p[0]) * 16 + fromhex (p[1]); + p += 2; + } + regcache_raw_supply (current_regcache, regnum, regp); + return 1; + } + + return 0; + } + static void remote_fetch_registers (int regnum) { *************** *** 3260,3265 **** --- 3308,3338 ---- "Attempt to fetch a non G-packet register when this " "remote.c does not support the p-packet."); } + switch (remote_protocol_p.support) + { + case PACKET_DISABLE: + break; + case PACKET_ENABLE: + if (fetch_register_using_p (regnum)) + return; + else + error ("Protocol error: p packet not recognized by stub"); + case PACKET_SUPPORT_UNKNOWN: + if (fetch_register_using_p (regnum)) + { + /* The stub recognized the 'p' packet. Remember this. */ + remote_protocol_p.support = PACKET_ENABLE; + return; + } + else + { + /* The stub does not support the 'P' packet. Use 'G' + instead, and don't try using 'P' in the future (it + will just waste our time). */ + remote_protocol_p.support = PACKET_DISABLE; + break; + } + } sprintf (buf, "g"); remote_send (buf, (rs->remote_packet_size)); *************** *** 5419,5424 **** --- 5492,5498 ---- show_remote_protocol_e_packet_cmd (args, from_tty, NULL); show_remote_protocol_E_packet_cmd (args, from_tty, NULL); show_remote_protocol_P_packet_cmd (args, from_tty, NULL); + show_remote_protocol_p_packet_cmd (args, from_tty, NULL); show_remote_protocol_qSymbol_packet_cmd (args, from_tty, NULL); show_remote_protocol_vcont_packet_cmd (args, from_tty, NULL); show_remote_protocol_binary_download_cmd (args, from_tty, NULL); *************** *** 5631,5636 **** --- 5705,5717 ---- &remote_set_cmdlist, &remote_show_cmdlist, 1); + add_packet_config_cmd (&remote_protocol_p, + "p", "fetch-register", + set_remote_protocol_p_packet_cmd, + show_remote_protocol_p_packet_cmd, + &remote_set_cmdlist, &remote_show_cmdlist, + 1); + add_packet_config_cmd (&remote_protocol_Z[Z_PACKET_SOFTWARE_BP], "Z0", "software-breakpoint", set_remote_protocol_Z_software_bp_packet_cmd,