more magic

walk/walk.c

@@ -12,14 +12,14 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include <dirent.h> /* closedir(3), opendir(3), readdir(3), DIR */
+#include <dirent.h> /* closedir(3), opendir(3), readdir(3), DIR,
+                     * struct dirent */
 #include <errno.h> /* errno */
 #include <stdio.h> /* fprintf(3), perror(3), stderr, stdout */
 #include <stdlib.h> /* realloc(3) */
-#include <string.h> /* strerror(3) */
-#include <sysexits.h> /* EX_OSERR, EX_USAGE */
-
-#include <getopt.h>
+#include <string.h> /* stpcpy(3), strcmp(3), strerror(3), strlen(3) */
+#include <sysexits.h> /* EX_OK, EX_INVALID, EX_OSERR, EX_USAGE */
+#include <unistd.h> /* getopt(3) */
 
 static char *dot[] = {".", NULL}; /* default (argc<2) */
 
@@ -38,9 +38,9 @@ fnprint(char *fn){
 
 static char *argv0;
 
-// Walks the directory named dirname, printing the names of all files it
-// contains (but not the name of the directory itself). Returns 2 if dirname is
-// not a directory and 1 if another error occurs.
+/* Walks the directory named dirname, printing the names of all files it
+ * contains (but not the name of the directory itself).
+ * Returns something other than EX_OK with errno set if an error occurs. */
 static int
 walk(char *dirname){
 	DIR dir;
@@ -50,23 +50,20 @@ walk(char *dirname){
 	char *np;
 	int retval;
 
-	if((dir = opendir(dirname)) == NULL){
-		fprintf(stdout, "%s: %s: %s\n",
-			argv0, dirname, strerror(errno));
-		return 1 + (errno == ENOTDIR);
-	}
+	fnprint(dirname);
+
+	if((dir = opendir(dirname)) == NULL)
+		return EX_NOINPUT;
 
 	errno = 0;
-	retval = 0;
 	while((f = readdir(dir)) != NULL){
 		if(strcmp(f->d_name, ".") == 0 || strcmp(f->d_name, "..") == 0)
 			continue;
 		if((l = strlen(dirname) + 1 + strlen(f->d_name) + 1)
 				> filename.a){
-			if((np = realloc(filename.p, l)) == NULL){
-				perror(argv0);
+			if((np = realloc(filename.p, l)) == NULL)
 				return EX_OSERR;
-			}else{
+			else{
 				filename.a = l;
 				filename.p = np; /* would you look at that */
 			}
@@ -74,19 +71,28 @@ walk(char *dirname){
 		stpcpy(stpcpy(stpcpy(filename.p, dirname), "/"), f->d_name);
 		/* TODO(bbaren@google.com): Emulate Plan 9's cleanname(3). */
 		fnprint(filename.p);
-		/* Walk the file if we can successfully open it as a directory.
-		 * Don't worry about it if it's not one (walk(filename) == 2). */
-		if ((f->d_type == DT_DIR || f->d_type == DT_UNKNOWN)
-				&& walk(filename.p) == 1)
-			retval = 1;
-	}
-	if(errno != 0 || closedir(dir) != NULL){
-		fprintf(stderr, "%s: %s: %s\n",
-			argv0, dirname, strerror(errno));
-		retval = 1;
+		/* Walk the file if we can successfully open it as a
+		 * directory. */
+		if(f->d_type == DT_DIR || f->d_type == DT_UNKNOWN){
+			if((retval = walk(filename.p)) != EX_OK){
+				if(retval == EX_OSERR)
+					return retval;
+				else{
+					fnprint(filename.p);
+					fprintf(stderr, "%s: %s: %s\n",
+						argv0, filename.p,
+						strerror(errno));
+				}
+			}
+		}else
+			fnprint(filename.p);
 	}
 
-	return retval;
+	if(errno != 0 || closedir(dir) != NULL)
+		fprintf(stderr, "%s: %s: %s\n",
+			argv0, dirname, strerror(errno));
+
+	return EX_OK;
 }
 
 int main(int argc, char *argv[]){
@@ -117,10 +123,15 @@ int main(int argc, char *argv[]){
 	if(*argv == NULL)
 		argv = dot;
 
-	while(*argv != NULL){
-		fnprint(*argv);
-		retval |= walk(*(argv++));
-	}
+	while(*argv != NULL)
+		if((retval = walk(*(argv++))) != EX_OK)
+			switch(retval){
+			case EX_OSERR: perror(argv0); return retval;
+			case EX_NOINPUT:
+				fprintf(stderr, "%s: %s: %s\n",
+					argv0, *(argv - 1), strerror(errno));
+				break;
+			}
 
-	return retval;
+	return EX_OK;
 }