Add liberror_pop_error and liberror_set_error_existing

Signed-off-by: Mattias Andrée <maandree@kth.se>

17 files changed, 189 insertions, 1 deletions

diff --git a/Makefile b/Makefile
index 6c17709..dc72232 100644
--- a/Makefile
+++ b/Makefile
@@ -23,12 +23,14 @@ OBJ =\
 	free_error.o\
 	get_error.o\
 	internal.o\
+	pop_error.o\
 	print_backtrace.o\
 	print_error.o\
 	reset_error.o\
 	save_backtrace.o\
 	set_error.o\
 	set_error_errno.o\
+	set_error_existing.o\
 	start.o
 
 MAN0 =\
@@ -39,12 +41,14 @@ MAN3 =\
 	liberror_end.3\
 	liberror_free_error.3\
 	liberror_get_error.3\
+	liberror_pop_error.3\
 	liberror_print_backtrace.3\
 	liberror_print_error.3\
 	liberror_reset_error.3\
 	liberror_save_backtrace.3\
 	liberror_set_error.3\
 	liberror_set_error_errno.3\
+	liberror_set_error_existing.3\
 	liberror_start.3
 
 MAN7 =\
diff --git a/liberror.h b/liberror.h
index 1e57502..4d222e6 100644
--- a/liberror.h
+++ b/liberror.h
@@ -354,6 +354,24 @@ void liberror_set_error(const char[256], const char[64], const char[64], long lo
 void liberror_set_error_errno(const char[256], const char[64], int);
 
 /**
+ * Remove the current error and, if the
+ * specified error is non-`NULL`, replace it
+ * with the the specified error
+ * 
+ * @param  error  The error to set as the current error, must not
+ *                be the pointer returned by liberror_get_error()
+ *                for any thread, including the current thread,
+ *                the function will copy and deallocate this error
+ */
+void liberror_set_error_existing(struct liberror_error *);
+
+/**
+ * Remove the current error and, if the error
+ * has a cause, replace it with its cause
+ */
+void liberror_pop_error(void);
+
+/**
  * The an error, its backtrace, and its
  * cause (recursively)
  * 
diff --git a/liberror_copy_error.3 b/liberror_copy_error.3
index 2bdf7a0..44d4999 100644
--- a/liberror_copy_error.3
+++ b/liberror_copy_error.3
@@ -49,10 +49,12 @@ None.
 .BR liberror_end (3),
 .BR liberror_free_error (3),
 .BR liberror_get_error (3),
+.BR liberror_pop_error (3),
 .BR liberror_print_backtrace (3),
 .BR liberror_print_error (3),
 .BR liberror_reset_error (3),
 .BR liberror_save_backtrace (3),
 .BR liberror_set_error (3),
 .BR liberror_set_error_errno (3),
+.BR liberror_set_error_existing (3),
 .BR liberror_start (3)
diff --git a/liberror_end.3 b/liberror_end.3
index bad6fbb..f32c692 100644
--- a/liberror_end.3
+++ b/liberror_end.3
@@ -41,10 +41,12 @@ None.
 .BR liberror_copy_error (3),
 .BR liberror_free_error (3),
 .BR liberror_get_error (3),
+.BR liberror_pop_error (3),
 .BR liberror_print_backtrace (3),
 .BR liberror_print_error (3),
 .BR liberror_reset_error (3),
 .BR liberror_save_backtrace (3),
 .BR liberror_set_error (3),
 .BR liberror_set_error_errno (3),
+.BR liberror_set_error_existing (3),
 .BR liberror_start (3)
diff --git a/liberror_free_error.3 b/liberror_free_error.3
index 9786e7f..10d7007 100644
--- a/liberror_free_error.3
+++ b/liberror_free_error.3
@@ -40,10 +40,12 @@ None.
 .BR liberror_copy_error (3),
 .BR liberror_end (3),
 .BR liberror_get_error (3),
+.BR liberror_pop_error (3),
 .BR liberror_print_backtrace (3),
 .BR liberror_print_error (3),
 .BR liberror_reset_error (3),
 .BR liberror_save_backtrace (3),
 .BR liberror_set_error (3),
 .BR liberror_set_error_errno (3),
+.BR liberror_set_error_existing (3),
 .BR liberror_start (3)
diff --git a/liberror_get_error.3 b/liberror_get_error.3
index aee173d..8059ada 100644
--- a/liberror_get_error.3
+++ b/liberror_get_error.3
@@ -48,10 +48,12 @@ None.
 .BR liberror_copy_error (3),
 .BR liberror_end (3),
 .BR liberror_free_error (3),
+.BR liberror_pop_error (3),
 .BR liberror_print_backtrace (3),
 .BR liberror_print_error (3),
 .BR liberror_reset_error (3),
 .BR liberror_save_backtrace (3),
 .BR liberror_set_error (3),
 .BR liberror_set_error_errno (3),
+.BR liberror_set_error_existing (3),
 .BR liberror_start (3)
diff --git a/liberror_pop_error.3 b/liberror_pop_error.3
new file mode 100644
index 0000000..61bcfbb
--- /dev/null
+++ b/liberror_pop_error.3
@@ -0,0 +1,52 @@
+.TH LIBERROR_POP_ERROR 3 2020-06-09 liberror
+.SH NAME
+liberror_pop_error \- replaces the current error with its cause
+.SH SYNOPSIS
+.nf
+#include <liberror.h>
+
+void liberror_pop_error(void);
+.fi
+.PP
+Link with
+.IR \-lerror .
+.SH DESCRIPTION
+The
+.BR liberror_pop_error ()
+function assigns the causal error for the
+current error set for the calling thread
+to the thread. If the thread does not have
+an error set, nothing will happen. If the
+thread's error does not have a cause, it
+will be reset without a replacement.
+.SH RETURN VALUE
+None.
+.SH ERRORS
+Failure to pop the error is impossible.
+.I errno
+will not be changed.
+.SH EXAMPLES
+None.
+.SH APPLICATION USAGE
+None.
+.SH RATIONALE
+None.
+.SH FUTURE DIRECTIONS
+None.
+.SH NOTES
+None.
+.SH SEE ALSO
+.BR liberror (7),
+.BR liberror.h (0),
+.BR liberror_copy_error (3),
+.BR liberror_end (3),
+.BR liberror_free_error (3),
+.BR liberror_get_error (3),
+.BR liberror_print_backtrace (3),
+.BR liberror_print_error (3),
+.BR liberror_reset_error (3),
+.BR liberror_save_backtrace (3),
+.BR liberror_set_error (3),
+.BR liberror_set_error_errno (3),
+.BR liberror_set_error_existing (3),
+.BR liberror_start (3)
diff --git a/liberror_print_bactrace.3 b/liberror_print_bactrace.3
index d8fb1ef..72a90d7 100644
--- a/liberror_print_bactrace.3
+++ b/liberror_print_bactrace.3
@@ -56,9 +56,11 @@ None.
 .BR liberror_end (3),
 .BR liberror_free_error (3),
 .BR liberror_get_error (3),
+.BR liberror_pop_error (3),
 .BR liberror_print_error (3),
 .BR liberror_reset_error (3),
 .BR liberror_save_backtrace (3),
 .BR liberror_set_error (3),
 .BR liberror_set_error_errno (3),
+.BR liberror_set_error_existing (3),
 .BR liberror_start (3)
diff --git a/liberror_print_error.3 b/liberror_print_error.3
index e6d390d..2a9f9d3 100644
--- a/liberror_print_error.3
+++ b/liberror_print_error.3
@@ -84,9 +84,11 @@ None.
 .BR liberror_end (3),
 .BR liberror_free_error (3),
 .BR liberror_get_error (3),
+.BR liberror_pop_error (3),
 .BR liberror_print_backtrace (3),
 .BR liberror_reset_error (3),
 .BR liberror_save_backtrace (3),
 .BR liberror_set_error (3),
 .BR liberror_set_error_errno (3),
+.BR liberror_set_error_existing (3),
 .BR liberror_start (3)
diff --git a/liberror_reset_error.3 b/liberror_reset_error.3
index 05050e8..0ed5d32 100644
--- a/liberror_reset_error.3
+++ b/liberror_reset_error.3
@@ -44,9 +44,11 @@ None.
 .BR liberror_end (3),
 .BR liberror_free_error (3),
 .BR liberror_get_error (3),
+.BR liberror_pop_error (3),
 .BR liberror_print_backtrace (3),
 .BR liberror_print_error (3),
 .BR liberror_save_backtrace (3),
 .BR liberror_set_error (3),
 .BR liberror_set_error_errno (3),
+.BR liberror_set_error_existing (3),
 .BR liberror_start (3)
diff --git a/liberror_save_backtrace.3 b/liberror_save_backtrace.3
index 371e5d2..cb7f94f 100644
--- a/liberror_save_backtrace.3
+++ b/liberror_save_backtrace.3
@@ -63,9 +63,11 @@ None.
 .BR liberror_end (3),
 .BR liberror_free_error (3),
 .BR liberror_get_error (3),
+.BR liberror_pop_error (3),
 .BR liberror_print_backtrace (3),
 .BR liberror_print_error (3),
 .BR liberror_reset_error (3),
 .BR liberror_set_error (3),
 .BR liberror_set_error_errno (3),
+.BR liberror_set_error_existing (3),
 .BR liberror_start (3)
diff --git a/liberror_set_error.3 b/liberror_set_error.3
index 23d4629..f2d74b0 100644
--- a/liberror_set_error.3
+++ b/liberror_set_error.3
@@ -96,9 +96,11 @@ None.
 .BR liberror_end (3),
 .BR liberror_free_error (3),
 .BR liberror_get_error (3),
+.BR liberror_pop_error (3),
 .BR liberror_print_backtrace (3),
 .BR liberror_print_error (3),
 .BR liberror_reset_error (3),
 .BR liberror_save_backtrace (3),
 .BR liberror_set_error_errno (3),
+.BR liberror_set_error_existing (3),
 .BR liberror_start (3)
diff --git a/liberror_set_error_errno.3 b/liberror_set_error_errno.3
index 1d68e90..e7f677b 100644
--- a/liberror_set_error_errno.3
+++ b/liberror_set_error_errno.3
@@ -42,9 +42,11 @@ None.
 .BR liberror_end (3),
 .BR liberror_free_error (3),
 .BR liberror_get_error (3),
+.BR liberror_pop_error (3),
 .BR liberror_print_backtrace (3),
 .BR liberror_print_error (3),
 .BR liberror_reset_error (3),
 .BR liberror_save_backtrace (3),
 .BR liberror_set_error (3),
+.BR liberror_set_error_existing (3),
 .BR liberror_start (3)
diff --git a/liberror_set_error_existing.3 b/liberror_set_error_existing.3
new file mode 100644
index 0000000..30c726d
--- /dev/null
+++ b/liberror_set_error_existing.3
@@ -0,0 +1,61 @@
+.TH LIBERROR_SET_ERROR_EXISTING 3 2020-06-09 liberror
+.SH NAME
+liberror_set_error_existing \- set the current error for the thread to a saved error
+.SH SYNOPSIS
+.nf
+#include <liberror.h>
+
+void liberror_set_error_existing(struct liberror_error *\fIerror\fP);
+.fi
+.PP
+Link with
+.IR \-lerror .
+.SH DESCRIPTION
+The
+.BR liberror_set_error_existing ()
+function assigns the error specified in the
+.I error
+parameter to the thread. If
+.I error
+is
+.BR NULL ,
+the current error will be removed without being
+replaces.
+.PP
+The pointer for the specified error will become
+invalid. The pointer for the specified error
+.B must not
+be the pointer returned by the
+.BR liberror_get_error (3)
+function.
+.SH RETURN VALUE
+None.
+.SH ERRORS
+Failure to set the error is impossible.
+.I errno
+will not be changed.
+.SH EXAMPLES
+None.
+.SH APPLICATION USAGE
+None.
+.SH RATIONALE
+None.
+.SH FUTURE DIRECTIONS
+None.
+.SH NOTES
+None.
+.SH SEE ALSO
+.BR liberror (7),
+.BR liberror.h (0),
+.BR liberror_copy_error (3),
+.BR liberror_end (3),
+.BR liberror_free_error (3),
+.BR liberror_get_error (3),
+.BR liberror_pop_error (3),
+.BR liberror_print_backtrace (3),
+.BR liberror_print_error (3),
+.BR liberror_reset_error (3),
+.BR liberror_save_backtrace (3),
+.BR liberror_set_error (3),
+.BR liberror_set_error_errno (3),
+.BR liberror_start (3)
diff --git a/liberror_start.3 b/liberror_start.3
index e4a09cd..8d4c240 100644
--- a/liberror_start.3
+++ b/liberror_start.3
@@ -45,9 +45,11 @@ None.
 .BR liberror_end (3),
 .BR liberror_free_error (3),
 .BR liberror_get_error (3),
+.BR liberror_pop_error (3),
 .BR liberror_print_backtrace (3),
 .BR liberror_print_error (3),
 .BR liberror_reset_error (3),
 .BR liberror_save_backtrace (3),
 .BR liberror_set_error (3),
-.BR liberror_set_error_errno (3)
+.BR liberror_set_error_errno (3),
+.BR liberror_set_error_existing (3)
diff --git a/pop_error.c b/pop_error.c
new file mode 100644
index 0000000..9f830a0
--- /dev/null
+++ b/pop_error.c
@@ -0,0 +1,14 @@
+/* See LICENSE file for copyright and license details. */
+#include "internal.h"
+
+
+void
+liberror_pop_error(void)
+{
+	struct liberror_error *cause;
+	if (liberror_have_error_) {
+		cause = liberror_error_.cause;
+		liberror_error_.cause = NULL;
+		liberror_set_error_existing(cause);
+	}
+}
diff --git a/set_error_existing.c b/set_error_existing.c
new file mode 100644
index 0000000..db6d6f1
--- /dev/null
+++ b/set_error_existing.c
@@ -0,0 +1,17 @@
+/* See LICENSE file for copyright and license details. */
+#include "internal.h"
+
+
+void
+liberror_set_error_existing(struct liberror_error *error)
+{
+	liberror_reset_error();
+	if (error) {
+		liberror_have_error_ = 1;
+		memcpy(&liberror_error_, error, sizeof(*error));
+		if (error->dynamically_allocated) {
+			liberror_error_.dynamically_allocated = 0;
+			free(error);
+		}
+	}
+}