Bug 568079: Cleanup of native code

* Unify pointer checkes
* Avoid using negated conditions.
* Reduce scope of local variables when possible

Change-Id: Ibacd13126351019af544f3e22513654d5ffee342
Signed-off-by: Torbjörn Svensson <azoff@svenskalinuxforeningen.se>

core/org.eclipse.cdt.core.native/native_src/unix/exec_pty.c

@@ -65,7 +65,7 @@ pid_t exec_pty(const char *path, char *const argv[], char *const envp[], const c
 
         chdir(dirpath);
 
-        if (channels != NULL) {
+        if (channels) {
             int fds;
 
             if (!console && setsid() < 0) {
@@ -116,10 +116,10 @@ pid_t exec_pty(const char *path, char *const argv[], char *const envp[], const c
             }
         }
 
-        if (envp[0] == NULL) {
-            execv(full_path, argv);
-        } else {
+        if (envp && envp[0]) {
             execve(full_path, argv, envp);
+        } else {
+            execv(full_path, argv);
         }
 
         _exit(127);
@@ -128,7 +128,7 @@ pid_t exec_pty(const char *path, char *const argv[], char *const envp[], const c
         if (console) {
             set_noecho(fdm);
         }
-        if (channels != NULL) {
+        if (channels) {
             channels[0] = fdm; /* Input Stream. */
             channels[1] = fdm; /* Output Stream.  */
             if (console) {
@@ -173,10 +173,10 @@ int main(int argc, char **argv, char **envp) {
         } else {
             fputs("foo\n", app_stdin);
             fputs("bar\n", app_stdin);
-            while (fgets(buffer, sizeof buffer, app_stdout) != NULL) {
+            while (fgets(buffer, sizeof buffer, app_stdout)) {
                 fprintf(stdout, "STDOUT: %s\n", buffer);
             }
-            while (fgets(buffer, sizeof buffer, app_stderr) != NULL) {
+            while (fgets(buffer, sizeof buffer, app_stderr)) {
                 fprintf(stdout, "STDERR: %s\n", buffer);
             }
         }

core/org.eclipse.cdt.core.native/native_src/unix/exec_unix.c

@@ -43,7 +43,7 @@ pid_t exec0(const char *path, char *const argv[], char *const envp[], const char
     /*
      * Make sure we can create our pipes before forking.
      */
-    if (channels != NULL) {
+    if (channels) {
         if (pipe(pipe0) < 0 || pipe(pipe1) < 0 || pipe(pipe2) < 0) {
             fprintf(stderr, "%s(%d): returning due to error.\n", __func__, __LINE__);
             free(full_path);
@@ -60,7 +60,7 @@ pid_t exec0(const char *path, char *const argv[], char *const envp[], const char
     } else if (childpid == 0) { /* child */
         chdir(dirpath);
 
-        if (channels != NULL) {
+        if (channels) {
             /* Close the write end of pipe0 */
             if (close(pipe0[1]) == -1) {
                 perror("close(pipe0[1])");
@@ -94,16 +94,16 @@ pid_t exec0(const char *path, char *const argv[], char *const envp[], const char
 
         setpgid(getpid(), getpid());
 
-        if (envp[0] == NULL) {
-            execv(full_path, argv);
-        } else {
+        if (envp && envp[0]) {
             execve(full_path, argv, envp);
+        } else {
+            execv(full_path, argv);
         }
 
         _exit(127);
 
     } else if (childpid != 0) { /* parent */
-        if (channels != NULL) {
+        if (channels) {
             /* close the read end of pipe1 */
             if (close(pipe0[0]) == -1) {
                 perror("close(pipe0[0])");

core/org.eclipse.cdt.core.native/native_src/unix/io.c

@@ -24,7 +24,7 @@
 static void ThrowByName(JNIEnv *env, const char *name, const char *msg) {
     jclass cls = (*env)->FindClass(env, name);
 
-    if (cls != 0) { /* Otherwise an exception has already been thrown */
+    if (cls) { /* Otherwise an exception has already been thrown */
         (*env)->ThrowNew(env, cls, msg);
     }
 

core/org.eclipse.cdt.core.native/native_src/unix/pfind.c

@@ -33,12 +33,11 @@
 const int path_def_len = 5; /* strlen(PATH_DEF); */
 
 char *path_val(char *const envp[]) {
-    int i;
-    if (envp == NULL || envp[0] == NULL) {
+    if (!envp || !envp[0]) {
         return getenv("PATH");
     }
 
-    for (i = 0; envp[i] != NULL; i++) {
+    for (int i = 0; envp[i]; i++) {
         char *p = envp[i];
         if (!strncmp(PATH_DEF, p, path_def_len)) {
             return p + path_def_len;
@@ -56,7 +55,7 @@ char *pfind(const char *name, char *const envp[]) {
     struct stat sb;
 
     /* Sanity check.  */
-    if (name == NULL) {
+    if (!name) {
         fprintf(stderr, "pfind(): Null argument.\n");
         return NULL;
     }
@@ -72,7 +71,7 @@ char *pfind(const char *name, char *const envp[]) {
     /* Search in the PATH environment. */
     path = path_val(envp);
 
-    if (path == NULL || strlen(path) <= 0) {
+    if (!path || strlen(path) <= 0) {
         fprintf(stderr, "Unable to get $PATH.\n");
         return NULL;
     }
@@ -81,7 +80,7 @@ char *pfind(const char *name, char *const envp[]) {
     path = strdup(path);
 
     tok = strtok_r(path, ":", &sp);
-    while (tok != NULL) {
+    while (tok) {
         snprintf(fullpath, sizeof(fullpath) - 1, "%s/%s", tok, name);
 
         if (stat(fullpath, &sb) == 0 && S_ISREG(sb.st_mode)) { /* fullpath is a file */
@@ -100,15 +99,12 @@ char *pfind(const char *name, char *const envp[]) {
 
 #ifdef BUILD_WITH_MAIN
 int main(int argc, char **argv) {
-    int i;
-    char *fullpath;
-
-    for (i = 1; i < argc; i++) {
-        fullpath = pfind(argv[i], NULL);
-        if (fullpath == NULL) {
-            printf("Unable to find %s in $PATH.\n", argv[i]);
-        } else {
+    for (int i = 1; i < argc; i++) {
+        char *fullpath = pfind(argv[i], NULL);
+        if (fullpath) {
             printf("Found %s @ %s.\n", argv[i], fullpath);
+        } else {
+            printf("Unable to find %s in $PATH.\n", argv[i]);
         }
     }
 }

core/org.eclipse.cdt.core.native/native_src/unix/pty.c

@@ -42,7 +42,7 @@ JNIEXPORT jstring JNICALL Java_org_eclipse_cdt_utils_pty_PTY_openMaster(JNIEnv *
 
         /* Set the master fd.  */
         fid = (*env)->GetFieldID(env, cls, "master", "I");
-        if (fid == NULL) {
+        if (!fid) {
             return NULL;
         }
         (*env)->SetIntField(env, jobj, fid, (jint)master);

core/org.eclipse.cdt.core.native/native_src/unix/spawner.c

@@ -102,17 +102,17 @@ JNIEXPORT jint JNICALL Java_org_eclipse_cdt_utils_spawner_Spawner_exec2(JNIEnv *
     int fd[3];
     pid_t pid = -1;
 
-    if (jchannels == NULL) {
+    if (!jchannels) {
         goto bail_out;
     }
 
     cmd = alloc_c_array(env, jcmd);
-    if (cmd == NULL) {
+    if (!cmd) {
         goto bail_out;
     }
 
     envp = alloc_c_array(env, jenv);
-    if (envp == NULL) {
+    if (!envp) {
         goto bail_out;
     }
 
@@ -151,12 +151,12 @@ JNIEXPORT jint JNICALL Java_org_eclipse_cdt_utils_spawner_Spawner_exec1(JNIEnv *
     pid_t pid = -1;
 
     cmd = alloc_c_array(env, jcmd);
-    if (cmd == NULL) {
+    if (!cmd) {
         goto bail_out;
     }
 
     envp = alloc_c_array(env, jenv);
-    if (envp == NULL) {
+    if (!envp) {
         goto bail_out;
     }
 
@@ -189,7 +189,7 @@ JNIEXPORT jint JNICALL Java_org_eclipse_cdt_utils_spawner_Spawner_exec0(JNIEnv *
     jclass channelClass = NULL;
     jmethodID channelConstructor = NULL;
 
-    if (jchannels == NULL) {
+    if (!jchannels) {
         goto bail_out;
     }
 
@@ -199,17 +199,17 @@ JNIEXPORT jint JNICALL Java_org_eclipse_cdt_utils_spawner_Spawner_exec0(JNIEnv *
     }
 
     channelConstructor = (*env)->GetMethodID(env, channelClass, "<init>", "(I)V");
-    if (channelConstructor == 0) {
+    if (!channelConstructor) {
         goto bail_out;
     }
 
     cmd = alloc_c_array(env, jcmd);
-    if (cmd == NULL) {
+    if (!cmd) {
         goto bail_out;
     }
 
     envp = alloc_c_array(env, jenv);
-    if (envp == NULL) {
+    if (!envp) {
         goto bail_out;
     }