From 6ef284bd18c31645eb3ec4e7691a0f07100d6b4e Mon Sep 17 00:00:00 2001 From: Simon Marchi Date: Mon, 2 Jun 2014 17:10:36 -0400 Subject: [PATCH] PR mi/15806: Fix quoting of async events Original patch: https://sourceware.org/ml/gdb-patches/2014-04/msg00552.html New in v2: * In remote.c:escape_buffer, pass '\\' to fputstrn_unfiltered/printchar to make sure backslashes are escaped in remote debug output. * Updated function documentation for printchar. See updated ChangeLog below. -------------------- The quoting in whatever goes in the event_channel of MI is little bit broken. Link for the lazy: https://sourceware.org/bugzilla/show_bug.cgi?id=15806 Here is an example of a =library-loaded event with an ill-named directory, /tmp/how"are\you (the problem is present with every directory on Windows since it uses backslashes as a path separator). The result will be the following: =library-loaded,id="/tmp/how"are\\you/libexpat.so.1",... The " between 'how' and 'are' should be escaped. Another bad behavior is double escaping in =breakpoint-created, for example: =breakpoint-created,bkpt={...,fullname="/tmp/how\\"are\\\\you/test.c",...} The two backslashes before 'how' should be one and the four before 'you' should be two. The reason for this is that when sending something to an MI console, escaping can take place at two different moments (the actual escaping work is always done in the printchar function): 1. When generating the content, if ui_out_field_* functions are used. Here, fields are automatically quoted with " and properly escaped. At least mi_field_string does it, not sure about mi_field_fmt, I need to investigate further. 2. When gdb_flush is called, to send the data in the buffer of the console to the actual output (stdout). At this point, mi_console_raw_packet takes the whole string in the buffer, quotes it, and escapes all occurences of the quoting character and backslashes. The event_channel does not specify a quoting character, so quotes are not escaped here, only backslashes. The problem with =library-loaded is that it does use fprintf_unfiltered, which doesn't do escaping (so, no #1). When gdb_flush is called, backslashes are escaped (#2). The problem with =breakpoint-created is that it first uses ui_out_field_* functions to generate its output, so backslashes and quotes are escaped there (#1). backslashes are escaped again in #2, leading to an overdose of backslashes. In retrospect, there is no way escaping can be done reliably in mi_console_raw_packet for data that is already formatted, such as event_channel. At this point, there is no way to differentiate quotes that delimit field values from those that should be escaped. In the case of other MI consoles, it is ok since mi_console_raw_packet receives one big string that should be quoted and escaped as a whole. So, first part of the fix: for the MI channels that specify no quoting character, no escaping at all should be done in mi_console_raw_packet (that's the change in printchar, thanks to Yuanhui Zhang for this). For those channels, whoever generates the content is responsible for proper quoting and escaping. This will fix the =breakpoint-created kind of problem. Second part of the fix is to make =library-loaded generate content that is properly escaped. For this, we use ui_out_field_* functions, instead of one big fprintf_unfiltered. =library-unloaded suffered from the same problem so it is modified as well. There might be other events that need fixing too, but that's all I found with a quick scan. Those that use fprintf_unfiltered but whose sole variable data is a %d are not critical, since it won't generate a " or a \. Finally, a test has been fixed, as it was expecting an erroneous output. Otherwise, all other tests that were previously passing still pass (x86-64 linux). gdb/ChangeLog: 2014-06-02 Simon Marchi PR mi/15806 * utils.c (printchar): Don't escape at all if quoter is NUL. Update function documentation to clarify effect of parameter QUOTER. * remote.c (escape_buffer): Pass '\\' as the quoter to fputstrn_unfiltered. * mi/mi-interp.c (mi_solib_loaded): Use ui_out_field_* functions to generate the output. (mi_solib_unloaded): Same. gdb/testsuite/ChangeLog: 2014-06-02 Simon Marchi * gdb.mi/mi-breakpoint-changed.exp (test_insert_delete_modify): Fix erroneous dprintf expected input. --- gdb/ChangeLog | 12 ++++++ gdb/mi/mi-interp.c | 57 ++++++++++++++------------ gdb/remote.c | 2 +- gdb/testsuite/ChangeLog | 5 +++ gdb/testsuite/gdb.mi/mi-breakpoint-changed.exp | 2 +- gdb/utils.c | 10 ++++- 6 files changed, 58 insertions(+), 30 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 1fd19f6..e671ff5 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,15 @@ +2014-06-05 Simon Marchi + + PR mi/15806 + * utils.c (printchar): Don't escape at all if quoter is NUL. + Update function documentation to clarify effect of parameter + QUOTER. + * remote.c (escape_buffer): Pass '\\' as the quoter to + fputstrn_unfiltered. + * mi/mi-interp.c (mi_solib_loaded): Use ui_out_field_* functions to + generate the output. + (mi_solib_unloaded): Same. + 2014-06-05 Joel Brobecker * development.sh: Delete. diff --git a/gdb/mi/mi-interp.c b/gdb/mi/mi-interp.c index 52a3a62..1b994e7 100644 --- a/gdb/mi/mi-interp.c +++ b/gdb/mi/mi-interp.c @@ -981,22 +981,24 @@ static void mi_solib_loaded (struct so_list *solib) { struct mi_interp *mi = top_level_interpreter_data (); + struct ui_out *uiout = interp_ui_out (top_level_interpreter ()); target_terminal_ours (); - if (gdbarch_has_global_solist (target_gdbarch ())) - fprintf_unfiltered (mi->event_channel, - "library-loaded,id=\"%s\",target-name=\"%s\"," - "host-name=\"%s\",symbols-loaded=\"%d\"", - solib->so_original_name, solib->so_original_name, - solib->so_name, solib->symbols_loaded); - else - fprintf_unfiltered (mi->event_channel, - "library-loaded,id=\"%s\",target-name=\"%s\"," - "host-name=\"%s\",symbols-loaded=\"%d\"," - "thread-group=\"i%d\"", - solib->so_original_name, solib->so_original_name, - solib->so_name, solib->symbols_loaded, - current_inferior ()->num); + + fprintf_unfiltered (mi->event_channel, "library-loaded"); + + ui_out_redirect (uiout, mi->event_channel); + + ui_out_field_string (uiout, "id", solib->so_original_name); + ui_out_field_string (uiout, "target-name", solib->so_original_name); + ui_out_field_string (uiout, "host-name", solib->so_name); + ui_out_field_int (uiout, "symbols-loaded", solib->symbols_loaded); + if (!gdbarch_has_global_solist (target_gdbarch ())) + { + ui_out_field_fmt (uiout, "thread-group", "i%d", current_inferior ()->num); + } + + ui_out_redirect (uiout, NULL); gdb_flush (mi->event_channel); } @@ -1005,20 +1007,23 @@ static void mi_solib_unloaded (struct so_list *solib) { struct mi_interp *mi = top_level_interpreter_data (); + struct ui_out *uiout = interp_ui_out (top_level_interpreter ()); target_terminal_ours (); - if (gdbarch_has_global_solist (target_gdbarch ())) - fprintf_unfiltered (mi->event_channel, - "library-unloaded,id=\"%s\",target-name=\"%s\"," - "host-name=\"%s\"", - solib->so_original_name, solib->so_original_name, - solib->so_name); - else - fprintf_unfiltered (mi->event_channel, - "library-unloaded,id=\"%s\",target-name=\"%s\"," - "host-name=\"%s\",thread-group=\"i%d\"", - solib->so_original_name, solib->so_original_name, - solib->so_name, current_inferior ()->num); + + fprintf_unfiltered (mi->event_channel, "library-unloaded"); + + ui_out_redirect (uiout, mi->event_channel); + + ui_out_field_string (uiout, "id", solib->so_original_name); + ui_out_field_string (uiout, "target-name", solib->so_original_name); + ui_out_field_string (uiout, "host-name", solib->so_name); + if (!gdbarch_has_global_solist (target_gdbarch ())) + { + ui_out_field_fmt (uiout, "thread-group", "i%d", current_inferior ()->num); + } + + ui_out_redirect (uiout, NULL); gdb_flush (mi->event_channel); } diff --git a/gdb/remote.c b/gdb/remote.c index 8f9478c..d5e5272 100644 --- a/gdb/remote.c +++ b/gdb/remote.c @@ -7082,7 +7082,7 @@ escape_buffer (const char *buf, int n) stb = mem_fileopen (); old_chain = make_cleanup_ui_file_delete (stb); - fputstrn_unfiltered (buf, n, 0, stb); + fputstrn_unfiltered (buf, n, '\\', stb); str = ui_file_xstrdup (stb, NULL); do_cleanups (old_chain); return str; diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 45f3512..3526388 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2014-06-05 Simon Marchi + + * gdb.mi/mi-breakpoint-changed.exp (test_insert_delete_modify): Fix + erroneous dprintf expected input. + 2014-06-04 Doug Evans * gdb.guile/scm-generics.exp: Delete. diff --git a/gdb/testsuite/gdb.mi/mi-breakpoint-changed.exp b/gdb/testsuite/gdb.mi/mi-breakpoint-changed.exp index aa991cf..70a7876 100644 --- a/gdb/testsuite/gdb.mi/mi-breakpoint-changed.exp +++ b/gdb/testsuite/gdb.mi/mi-breakpoint-changed.exp @@ -96,7 +96,7 @@ proc test_insert_delete_modify { } { $test set test "dprintf marker, \"arg\" \"" mi_gdb_test $test \ - {.*=breakpoint-created,bkpt=\{number="6",type="dprintf".*,script=\{\"printf \\\\\"arg\\\\\" \\\\\"\"\}.*\}\r\n\^done} \ + {.*=breakpoint-created,bkpt=\{number="6",type="dprintf".*,script=\{\"printf \\\"arg\\\" \\\"\"\}.*\}\r\n\^done} \ $test # 2. when modifying condition diff --git a/gdb/utils.c b/gdb/utils.c index 6e8f384..f61974d 100644 --- a/gdb/utils.c +++ b/gdb/utils.c @@ -1502,7 +1502,13 @@ parse_escape (struct gdbarch *gdbarch, const char **string_ptr) /* Print the character C on STREAM as part of the contents of a literal string whose delimiter is QUOTER. Note that this routine should only be call for printing things which are independent of the language - of the program being debugged. */ + of the program being debugged. + + printchar will normally escape backslashes and instances of QUOTER. If + QUOTER is 0, printchar won't escape backslashes or any quoting character. + As a side effect, if you pass the backslash character as the QUOTER, + printchar will escape backslashes as usual, but not any other quoting + character. */ static void printchar (int c, void (*do_fputs) (const char *, struct ui_file *), @@ -1545,7 +1551,7 @@ printchar (int c, void (*do_fputs) (const char *, struct ui_file *), } else { - if (c == '\\' || c == quoter) + if (quoter != 0 && (c == '\\' || c == quoter)) do_fputs ("\\", stream); do_fprintf (stream, "%c", c); } -- 2.7.4