Date: Thu, 22 Aug 2019 00:19:41 +0000 (UTC) From: Conrad Meyer <cem@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r351366 - head/sys/gdb Message-ID: <201908220019.x7M0JfYc076453@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: cem Date: Thu Aug 22 00:19:41 2019 New Revision: 351366 URL: https://svnweb.freebsd.org/changeset/base/351366 Log: gdb(4): Add basic 'qSupported' support This is where the host GDB tells us what features it supports, and we respond with the list we support. For now, just report PacketSize. Modified: head/sys/gdb/gdb_main.c Modified: head/sys/gdb/gdb_main.c ============================================================================== --- head/sys/gdb/gdb_main.c Thu Aug 22 00:19:14 2019 (r351365) +++ head/sys/gdb/gdb_main.c Thu Aug 22 00:19:41 2019 (r351366) @@ -162,12 +162,117 @@ sendit: gdb_tx_end(); } +#define BIT(n) (1ull << (n)) +enum { + GDB_MULTIPROCESS, + GDB_SWBREAK, + GDB_HWBREAK, + GDB_QRELOCINSN, + GDB_FORK_EVENTS, + GDB_VFORK_EVENTS, + GDB_EXEC_EVENTS, + GDB_VCONT_SUPPORTED, + GDB_QTHREADEVENTS, + GDB_NO_RESUMED, +}; +static const char * const gdb_feature_names[] = { + [GDB_MULTIPROCESS] = "multiprocess", + [GDB_SWBREAK] = "swbreak", + [GDB_HWBREAK] = "hwbreak", + [GDB_QRELOCINSN] = "qRelocInsn", + [GDB_FORK_EVENTS] = "fork-events", + [GDB_VFORK_EVENTS] = "vfork-events", + [GDB_EXEC_EVENTS] = "exec-events", + [GDB_VCONT_SUPPORTED] = "vContSupported", + [GDB_QTHREADEVENTS] = "QThreadEvents", + [GDB_NO_RESUMED] = "no-resumed", +}; +static void +gdb_do_qsupported(uint32_t *feat) +{ + char *tok, *delim, ok; + size_t i, toklen; + + /* Parse supported host features */ + *feat = 0; + if (gdb_rx_char() != ':') + goto error; + + while (gdb_rxsz > 0) { + tok = gdb_rxp; + delim = strchrnul(gdb_rxp, ';'); + toklen = (delim - tok); + + gdb_rxp += toklen; + gdb_rxsz -= toklen; + if (*delim != '\0') { + *delim = '\0'; + gdb_rxp += 1; + gdb_rxsz -= 1; + } + + if (toklen < 2) + goto error; + + ok = tok[toklen - 1]; + if (ok != '-' && ok != '+') { + /* + * GDB only has one KV-pair feature, and we don't + * support it, so ignore and move on. + */ + if (strchr(tok, '=') != NULL) + continue; + /* Not a KV-pair, and not a +/- flag? Malformed. */ + goto error; + } + if (ok != '+') + continue; + tok[toklen - 1] = '\0'; + + for (i = 0; i < nitems(gdb_feature_names); i++) + if (strcmp(gdb_feature_names[i], tok) == 0) + break; + + if (i == nitems(gdb_feature_names)) { + /* Unknown GDB feature. */ + continue; + } + + *feat |= BIT(i); + } + + /* Send a supported feature list back */ + gdb_tx_begin(0); + + gdb_tx_str("PacketSize"); + gdb_tx_char('='); + /* + * We don't buffer framing bytes, but we do need to retain a byte for a + * trailing nul. + */ + gdb_tx_varhex(GDB_BUFSZ + strlen("$#nn") - 1); + + /* + * Future consideration: + * - vCont + * - multiprocess + * - qXfer:threads:read + */ + gdb_tx_end(); + return; + +error: + *feat = 0; + gdb_tx_err(EINVAL); +} + static int gdb_trap(int type, int code) { jmp_buf jb; struct thread *thr_iter; void *prev_jb; + uint32_t host_features; prev_jb = kdb_jmpbuf(jb); if (setjmp(jb) != 0) { @@ -313,6 +418,8 @@ gdb_trap(int type, int code) gdb_tx_char('C'); gdb_tx_varhex((long)kdb_thread->td_tid); gdb_tx_end(); + } else if (gdb_rx_equal("Supported")) { + gdb_do_qsupported(&host_features); } else if (gdb_rx_equal("fThreadInfo")) { thr_iter = kdb_thr_first(); gdb_do_threadinfo(&thr_iter);
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201908220019.x7M0JfYc076453>