[Ltrace-devel] [PATCH] check return value of unw_get_reg and unw_get_proc_name

[Luca Clementi]

Before printng the current procedure name and IP verify their validity
---
 output.c |   16 ++++++++++++----
 proc.c   |    5 -----
 proc.h   |    1 +
 3 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/output.c b/output.c
index 82b6a5e..417d370 100644
--- a/output.c
+++ b/output.c
@@ -661,9 +661,11 @@ output_right(enum tof type, struct process *proc, struct library_symbol *libsym,
 					!= sizeof(arch_addr_t))]);
 		unw_init_remote(&cursor, proc->unwind_as, proc->unwind_priv);
 		while (unwind_depth) {
-			unw_get_reg(&cursor, UNW_REG_IP, (unw_word_t *) &ip);
-			unw_get_proc_name(&cursor, fn_name, sizeof(fn_name),
-					(unw_word_t *) &function_offset);
+
+			if (unw_get_reg(&cursor, UNW_REG_IP, (unw_word_t *) &ip)) {
+				fprintf(options.output, " > stacktrace_error\n");
+				continue;
+			}
 
 			/* We are looking for the library with the base address
 			 * closest to the current ip.  */
@@ -683,8 +685,14 @@ output_right(enum tof type, struct process *proc, struct library_symbol *libsym,
 				lib = lib->next;
 			}
 
-			fprintf(options.output, " > %s(%s+0x%p) [%p]\n",
+			own_retval = unw_get_proc_name(&cursor, fn_name, sizeof(fn_name),
+						(unw_word_t *) &function_offset);
+			if ((own_retval == 0) || (own_retval == -UNW_ENOMEM))
+				fprintf(options.output, " > %s(%s+%p) [%p]\n",
 					lib_name, fn_name, function_offset, ip);
+			else
+				fprintf(options.output, " > %s(error) [%p]\n",
+					lib_name, ip);
 
 			if (unw_step(&cursor) <= 0)
 				break;
diff --git a/proc.c b/proc.c
index 11755b0..97bcb60 100644
--- a/proc.c
+++ b/proc.c
@@ -29,11 +29,6 @@
 #include <stdlib.h>
 #include <string.h>
 
-#if defined(HAVE_LIBUNWIND)
-#include <libunwind.h>
-#include <libunwind-ptrace.h>
-#endif /* defined(HAVE_LIBUNWIND) */
-
 #include "backend.h"
 #include "breakpoint.h"
 #include "debug.h"
diff --git a/proc.h b/proc.h
index 64f8fe2..35943c3 100644
--- a/proc.h
+++ b/proc.h
@@ -30,6 +30,7 @@
 
 #if defined(HAVE_LIBUNWIND)
 # include <libunwind.h>
+# include <libunwind-ptrace.h>
 #endif /* defined(HAVE_LIBUNWIND) */
 
 #include "ltrace.h"
-- 
1.7.9.5