1 // SPDX-License-Identifier: CDDL-1.0
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or https://opensource.org/licenses/CDDL-1.0.
33  * Output helpers. libspl_backtrace() must not block, must be thread-safe and
35  * printf, so we end up having to call write() directly on the fd. That's
40 #define	spl_bt_write_n(fd, s, n) \  argument
41 	do { ssize_t r __maybe_unused = write(fd, s, n); } while (0)
42 #define	spl_bt_write(fd, s)		spl_bt_write_n(fd, s, sizeof (s)-1)  argument
46  * libunwind-gcc and libunwind-llvm both list registers using an enum,
48  * a given architecture in different ways. We can check which one is defined
66  * Convert `v` to ASCII hex characters. The bottom `n` nybbles (4-bits ie one
68  * null-terminated. Returns the number of digits written.
80 	for (int i = 15; i >= 0; i--) {  in spl_bt_u64_to_hex_str()
94 libspl_backtrace(int fd)  in libspl_backtrace()  argument
113 	 * top frame, and show them, with names, in a nice three-column  in libspl_backtrace()
116 	spl_bt_write(fd, "Registers:\n");  in libspl_backtrace()
132 	 * register must exist, and so we get its name. If libunwind has no  in libspl_backtrace()
135 	 * shouldn't really matter. We can see the value, and that's the main  in libspl_backtrace()
159 		 * is an alternate end-of-string character. LLVM libunwind will  in libspl_backtrace()
171 			 * No valid name, or likely llvm_libunwind returned  in libspl_backtrace()
173 			 * where "xx" is the two-char hex of libunwind's  in libspl_backtrace()
178 			    &buf[1], sizeof (buf)-1) + 1;  in libspl_backtrace()
186 		spl_bt_write_n(fd, "      ", 5-MIN(n, 3));  in libspl_backtrace()
189 		spl_bt_write_n(fd, name, n);  in libspl_backtrace()
190 		spl_bt_write(fd, ": 0x");  in libspl_backtrace()
194 		 * assuming that all registers are 64-bits wide, which is  in libspl_backtrace()
195 		 * probably fine for any general-purpose registers on any  in libspl_backtrace()
201 		spl_bt_write_n(fd, buf, n);  in libspl_backtrace()
205 			spl_bt_write(fd, "\n");  in libspl_backtrace()
210 		spl_bt_write(fd, "\n");  in libspl_backtrace()
213 	spl_bt_write(fd, "Call trace:\n");  in libspl_backtrace()
221 		 * specially, because its used a lot internally. Still, no  in libspl_backtrace()
227 			spl_bt_write(fd, "  [couldn't get IP register; "  in libspl_backtrace()
234 		spl_bt_write(fd, "  [0x");  in libspl_backtrace()
235 		spl_bt_write_n(fd, buf, n);  in libspl_backtrace()
236 		spl_bt_write(fd, "] ");  in libspl_backtrace()
243 		 * If libunwind can't determine the name, we just show "???"  in libspl_backtrace()
252 		if (err == 0 || err == -UNW_ENOMEM) {  in libspl_backtrace()
254 			spl_bt_write_n(fd, buf, n);  in libspl_backtrace()
257 			spl_bt_write(fd, "+0x");  in libspl_backtrace()
259 			spl_bt_write_n(fd, buf, n);  in libspl_backtrace()
261 			spl_bt_write(fd, "???");  in libspl_backtrace()
272 		if (err == 0 || err == -UNW_ENOMEM) {  in libspl_backtrace()
274 			spl_bt_write(fd, " (in ");  in libspl_backtrace()
275 			spl_bt_write_n(fd, buf, n);  in libspl_backtrace()
278 			spl_bt_write(fd, " +0x");  in libspl_backtrace()
280 			spl_bt_write_n(fd, buf, n);  in libspl_backtrace()
281 			spl_bt_write(fd, ")");  in libspl_backtrace()
284 		spl_bt_write(fd, "\n");  in libspl_backtrace()
291 libspl_backtrace(int fd)  in libspl_backtrace()  argument
295 	spl_bt_write(fd, "Call trace:\n");  in libspl_backtrace()
296 	backtrace_symbols_fd(btptrs, nptrs, fd);  in libspl_backtrace()
300 libspl_backtrace(int fd __maybe_unused)  in libspl_backtrace()