[PATCH] analyzer: add get_meaning_for_state_change vfunc to fd_diagnostic in sm-fd.cc [PR106286]

[Immad Mir <mirimmad@outlook.com>]

This patch adds get_meaning_for_state_change vfunc to
fd_diagnostic in sm-fd.cc which could be used by SARIF output.

Lightly tested on x86_64 Linux.

gcc/analyzer/ChangeLog:
	PR analyzer/106286
	* sm-fd.cc:
	(fd_diagnostic::get_meaning_for_state_change): New.

gcc/testsuite/ChangeLog:
	PR analyzer/106286
	* gcc.dg/analyzer/fd-meaning.c: New test.

Signed-off-by: Immad Mir <mirimmad@outlook.com>
---
 gcc/analyzer/sm-fd.cc                      | 14 ++++++++
 gcc/testsuite/gcc.dg/analyzer/fd-meaning.c | 37 ++++++++++++++++++++++
 2 files changed, 51 insertions(+)
 create mode 100644 gcc/testsuite/gcc.dg/analyzer/fd-meaning.c

diff --git a/gcc/analyzer/sm-fd.cc b/gcc/analyzer/sm-fd.cc
index 56b0063ba42..ed923ade100 100644
--- a/gcc/analyzer/sm-fd.cc
+++ b/gcc/analyzer/sm-fd.cc
@@ -229,6 +229,20 @@ public:
     return label_text ();
   }
 
+  diagnostic_event::meaning
+  get_meaning_for_state_change (
+      const evdesc::state_change &change) const final override
+  {
+    if (change.m_old_state == m_sm.get_start_state ()
+		&& (m_sm.is_unchecked_fd_p (change.m_new_state)))
+      return diagnostic_event::meaning (diagnostic_event::VERB_acquire,
+			 diagnostic_event::NOUN_resource);
+    if (change.m_new_state == m_sm.m_closed)
+      return diagnostic_event::meaning (diagnostic_event::VERB_release,
+			 diagnostic_event::NOUN_resource);
+    return diagnostic_event::meaning ();
+  }
+
 protected:
   const fd_state_machine &m_sm;
   tree m_arg;
diff --git a/gcc/testsuite/gcc.dg/analyzer/fd-meaning.c b/gcc/testsuite/gcc.dg/analyzer/fd-meaning.c
new file mode 100644
index 00000000000..6a9ec921fd3
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/analyzer/fd-meaning.c
@@ -0,0 +1,37 @@
+  /* { dg-additional-options "-fanalyzer-verbose-state-changes" } */
+int open(const char *, int mode);
+void close(int fd);
+
+#define O_RDONLY 0
+#define O_WRONLY 1
+#define O_RDWR 2
+
+void test_1 (const char* path)
+{
+    int fd = open (path, O_RDWR); /* { dg-message "meaning: \\{verb: 'acquire', noun: 'resource'\\}" } */
+    if (fd != -1)
+    {
+        close(fd); /* { dg-message "meaning: \\{verb: 'release', noun: 'resource'\\}" } */
+        close(fd); /* { dg-warning "double 'close' of file descriptor 'fd' \\\[CWE-1341\\\]" } */
+    }
+}
+
+void test_2 (const char* path)
+{
+    int fd = open (path, O_RDONLY); /* { dg-message "meaning: \\{verb: 'acquire', noun: 'resource'\\}" } */
+    if (fd != -1)
+    {
+        close(fd); /* { dg-message "meaning: \\{verb: 'release', noun: 'resource'\\}" } */
+        close(fd); /* { dg-warning "double 'close' of file descriptor 'fd' \\\[CWE-1341\\\]" } */
+    }
+}
+
+void test_3 (const char* path)
+{
+    int fd = open (path, O_WRONLY); /* { dg-message "meaning: \\{verb: 'acquire', noun: 'resource'\\}" } */
+    if (fd != -1)
+    {
+        close(fd); /* { dg-message "meaning: \\{verb: 'release', noun: 'resource'\\}" } */
+        close(fd); /* { dg-warning "double 'close' of file descriptor 'fd' \\\[CWE-1341\\\]" } */
+    }
+}
\ No newline at end of file
-- 
2.25.1