From 74d8fa2df7e7844f9b1b8fac27fe7d0b82100ab0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=D0=A1=D0=B5=D1=80=D0=B3=D0=B5=D0=B9=20=D0=A7=D0=B5=D1=80?= =?UTF-8?q?=D0=BD=D0=BE=D0=B2?= Date: Fri, 19 Jan 2024 11:01:18 -0700 Subject: Fix remote serial read MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit After closing "Bug 30770 - serial.c does not preserve errno correctly" https://sourceware.org/bugzilla/show_bug.cgi?id=30770 remote debugging became impossible due to an attempt to recv() by a call intended for the socket, and not for the character device file. The documentation implicitly states that it is possible to use the read() call to work with a socket. But this does not mean in the general case that it is permissible to use recv in the case of a non-socket. condition: os: Distributor ID: Ubuntu Description: Ubuntu 23.10 Release: 23.10 Codename: mantic libc: ldd (Ubuntu GLIBC 2.38-1ubuntu6) 2.38 kernel: Linux klen-dev-um790pro 6.5.0-14-generic #14-Ubuntu SMP PREEMPT_DYNAMIC Tue Nov 14 14:59:49 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux gdb: build from trank at 15.0.50.20231226-git GDB output: $ arm-kgp-eabi-gdb GNU gdb (Klen's_GNU_package_(KGP)_for_target::arm-kgp-eabi_host::x86_64-kgp-linux-gnu_znver4-avx512<<ílex>>) 15.0.50.20231226-git .... (gdb) tar ext /dev/ttyACM1 Remote debugging using /dev/ttyACM1 Remote communication error. Target disconnected: error while reading: Socket operation on non-socket. (gdb) after fix gdb work fine $ arm-kgp-eabi-gdb -q (gdb) tar ext /dev/ttyACM0 Remote debugging using /dev/ttyACM0 (gdb) mon swd Target voltage: 0.0V Available Targets: No. Att Driver STM32F40x M4 (gdb) att 1 Attaching to Remote target warning: No executable has been specified and target does not support determining executable automatically. Try using the "file" command. 0x08020c80 in ?? () (gdb) Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30770 --- gdb/ser-unix.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/gdb/ser-unix.c b/gdb/ser-unix.c index f917aa85e3d..bc8b087b6eb 100644 --- a/gdb/ser-unix.c +++ b/gdb/ser-unix.c @@ -574,7 +574,7 @@ when debugging using remote targets."), int ser_unix_read_prim (struct serial *scb, size_t count) { - int result = recv (scb->fd, scb->buf, count, 0); + int result = read (scb->fd, scb->buf, count); if (result == -1 && errno != EINTR) perror_with_name ("error while reading"); return result; -- cgit v1.2.3