From 32cd7d727d66d039dbf297164b557224f864b9e3 Mon Sep 17 00:00:00 2001
From: orbitcowboy <ettl.martin78@gmail.com>
Date: Mon, 15 Dec 2014 10:05:44 +0100
Subject: [PATCH] Fixed #6325: false negative: uninitialized variable usage
 (write, posix).

---
 cfg/posix.cfg          |  1 +
 test/testuninitvar.cpp | 61 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 62 insertions(+)

diff --git a/cfg/posix.cfg b/cfg/posix.cfg
index 3ab0a1b3c..0a7a888ea 100644
--- a/cfg/posix.cfg
+++ b/cfg/posix.cfg
@@ -287,6 +287,7 @@
     </arg>
     <arg nr="2">
       <minsize type="argvalue" arg="3"/>
+      <not-uninit/>
     </arg>
     <arg nr="3">
       <not-uninit/>
diff --git a/test/testuninitvar.cpp b/test/testuninitvar.cpp
index a17917e8b..362d2b731 100644
--- a/test/testuninitvar.cpp
+++ b/test/testuninitvar.cpp
@@ -77,6 +77,8 @@ private:
 
         // dead pointer
         TEST_CASE(deadPointer);
+
+        TEST_CASE(uninitvar_posix_write);
     }
 
     void checkUninitVar(const char code[], const char filename[] = "test.cpp") {
@@ -3873,6 +3875,65 @@ private:
                          "}");
         ASSERT_EQUALS("", errout.str());
     }
+
+    void uninitvar_posix_write() { // #6325
+        // Load posix library file
+        LOAD_LIB_2(settings.library, "posix.cfg");
+
+        // check the first parameter of write
+        checkUninitVar("void uninitvar(char *buf)\n"
+                       "{\n"
+                       "    int fd;\n"
+                       "    write(fd, buf, sizeof(buf));\n"
+                       "}");
+        ASSERT_EQUALS("[test.cpp:4]: (error) Uninitialized variable: fd\n", errout.str());
+
+        checkUninitVar("void no_uninitvar(int fd, char *buf)\n"
+                       "{\n"
+                       "    write(fd, buf, sizeof(buf));\n"
+                       "}");
+        ASSERT_EQUALS("", errout.str());
+
+
+        // check the second parameter of the posix function write
+        checkUninitVar("void uninitvar() {\n"
+                       "    char *buf;\n"
+                       "    write(STDOUT_FILENO, buf, sizeof(buf));\n"
+                       "}");
+        ASSERT_EQUALS("[test.cpp:3]: (error) Uninitialized variable: buf\n", errout.str());
+
+        checkUninitVar("void uninitvar() {\n"
+                       "    char buf[2];\n"
+                       "    write(STDOUT_FILENO, buf, 2);\n"
+                       "}");
+        ASSERT_EQUALS("[test.cpp:3]: (error) Uninitialized variable: buf\n", errout.str());
+
+        // avoid false positives
+        checkUninitVar("void no_uninitvar(char *buf) {\n"
+                       "    write(STDOUT_FILENO, buf, sizeof(buf));\n"
+                       "}");
+        ASSERT_EQUALS("", errout.str());
+
+        checkUninitVar("void no_uninitvar() {\n"
+                       "    char buf[1] = {'c'};\n"
+                       "    write(STDOUT_FILENO, &buf, 1);\n"
+                       "}");
+        ASSERT_EQUALS("", errout.str());
+
+
+        // check the third parameter of the posix function write
+        checkUninitVar("void uninitvar(char *buf) {\n"
+                       "    int nbytes;\n"
+                       "    write(STDOUT_FILENO, buf, nbytes);\n"
+                       "}");
+        TODO_ASSERT_EQUALS("[test.cpp:3]: (error) Uninitialized variable: nbytes\n", "", errout.str());
+
+        checkUninitVar("void no_uninitvar(char *buf, int nbytes)\n"
+                       "{\n"
+                       "    write(STDOUT_FILENO, buf, nbytes);\n"
+                       "}");
+        ASSERT_EQUALS("", errout.str());
+    }
 };
 
 REGISTER_TEST(TestUninitVar)