From 3347eb1acf1a59339d00749fafbb901be9325cd4 Mon Sep 17 00:00:00 2001 From: xuepeng guo Date: Wed, 18 Jul 2012 04:36:24 +0000 Subject: [PATCH] 2012-07-18 Terry Guo PR 14329 * defs.h (GDB_MI_MSG_WIDTH): New. * ser_base (ser_base_read_error_fd): New function. (do_ser_base_readchar): Poll error file descriptor as well as standard output. (generic_readchar): Refactor error handling. --- gdb/ChangeLog | 9 ++++ gdb/defs.h | 3 ++ gdb/ser-base.c | 113 +++++++++++++++++++++++++++++-------------------- 3 files changed, 78 insertions(+), 47 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index acd5b5e6b09..9bd7d6e0b69 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,12 @@ +2012-07-18 Terry Guo + + PR 14329 + * defs.h (GDB_MI_MSG_WIDTH): New. + * ser_base (ser_base_read_error_fd): New function. + (do_ser_base_readchar): Poll error file descriptor as well as + standard output. + (generic_readchar): Refactor error handling. + 2012-07-18 Joel Brobecker * NEWS: Create a new section for the next release branch. diff --git a/gdb/defs.h b/gdb/defs.h index 1c6fa7941ca..bd556b0ccb5 100644 --- a/gdb/defs.h +++ b/gdb/defs.h @@ -1115,6 +1115,9 @@ extern int use_windows; #define ISATTY(FP) (isatty (fileno (FP))) #endif +/* A width that can achieve a better legibility for GDB MI mode. */ +#define GDB_MI_MSG_WIDTH 80 + /* Ensure that V is aligned to an N byte boundary (B's assumed to be a power of 2). Round up/down when necessary. Examples of correct use include: diff --git a/gdb/ser-base.c b/gdb/ser-base.c index 2f12dfcdc17..287e55d2af6 100644 --- a/gdb/ser-base.c +++ b/gdb/ser-base.c @@ -25,6 +25,7 @@ #include "gdb_select.h" #include "gdb_string.h" +#include "gdb_assert.h" #include #ifdef USE_WIN32API #include @@ -242,6 +243,64 @@ ser_base_wait_for (struct serial *scb, int timeout) } } +/* Read any error output we might have. */ + +static void +ser_base_read_error_fd (struct serial *scb, int close_fd) +{ + if (scb->error_fd != -1) + { + ssize_t s; + char buf[GDB_MI_MSG_WIDTH + 1]; + + for (;;) + { + char *current; + char *newline; + int to_read = GDB_MI_MSG_WIDTH; + int num_bytes = -1; + + if (scb->ops->avail) + num_bytes = (scb->ops->avail)(scb, scb->error_fd); + + if (num_bytes != -1) + to_read = (num_bytes < to_read) ? num_bytes : to_read; + + if (to_read == 0) + break; + + s = read (scb->error_fd, &buf, to_read); + if ((s == -1) || (s == 0 && !close_fd)) + break; + + if (s == 0 && close_fd) + { + /* End of file. */ + close (scb->error_fd); + scb->error_fd = -1; + break; + } + + /* In theory, embedded newlines are not a problem. + But for MI, we want each output line to have just + one newline for legibility. So output things + in newline chunks. */ + gdb_assert (s > 0 && s <= GDB_MI_MSG_WIDTH); + buf[s] = '\0'; + current = buf; + while ((newline = strstr (current, "\n")) != NULL) + { + *newline = '\0'; + fputs_unfiltered (current, gdb_stderr); + fputs_unfiltered ("\n", gdb_stderr); + current = newline + 1; + } + + fputs_unfiltered (current, gdb_stderr); + } + } +} + /* Read a character with user-specified timeout. TIMEOUT is number of seconds to wait, or -1 to wait forever. Use timeout of 0 to effect a poll. Returns char if successful. Returns -2 if timeout expired, EOF if line dropped @@ -292,6 +351,11 @@ do_ser_base_readchar (struct serial *scb, int timeout) status = SERIAL_TIMEOUT; break; } + + /* We also need to check and consume the stderr because it could + come before the stdout for some stubs. If we just sit and wait + for stdout, we would hit a deadlock for that case. */ + ser_base_read_error_fd (scb, 0); } if (status < 0) @@ -362,54 +426,9 @@ generic_readchar (struct serial *scb, int timeout, } } } - /* Read any error output we might have. */ - if (scb->error_fd != -1) - { - ssize_t s; - char buf[81]; - - for (;;) - { - char *current; - char *newline; - int to_read = 80; - - int num_bytes = -1; - if (scb->ops->avail) - num_bytes = (scb->ops->avail)(scb, scb->error_fd); - if (num_bytes != -1) - to_read = (num_bytes < to_read) ? num_bytes : to_read; - - if (to_read == 0) - break; - - s = read (scb->error_fd, &buf, to_read); - if (s == -1) - break; - if (s == 0) - { - /* EOF */ - close (scb->error_fd); - scb->error_fd = -1; - break; - } - /* In theory, embedded newlines are not a problem. - But for MI, we want each output line to have just - one newline for legibility. So output things - in newline chunks. */ - buf[s] = '\0'; - current = buf; - while ((newline = strstr (current, "\n")) != NULL) - { - *newline = '\0'; - fputs_unfiltered (current, gdb_stderr); - fputs_unfiltered ("\n", gdb_stderr); - current = newline + 1; - } - fputs_unfiltered (current, gdb_stderr); - } - } + /* Read any error output we might have. */ + ser_base_read_error_fd (scb, 1); reschedule (scb); return ch; -- 2.30.2