Fix #939, rework shell test

src/tests/shell-test/shell-test.c

@@ -30,15 +30,36 @@
 
 #define OS_TEST_SHELL_FILENAME "/drive0/shell_test.txt"
 
+const char OS_TEST_SHELL_COMMAND[] = "echo";
+const char OS_TEST_SHELL_STRING[]  = "ValueToEchoInTheFile";
+
+/*
+ * Extra chars to allow for quoting and whitespace.
+ *
+ * There needs to be spaces between arguments, and depending
+ * on the shell config and its behavior it may echo extra whitespace
+ * and/or other chars, and a newline itself may be multiple chars (CR+LF).
+ *
+ * This allows up to this many extra chars surrounding the test string.
+ */
+#define OS_TEST_SHELL_MAX_EXTRA_CHARS 8
+
+/*
+ * Sizes for the echo buffer and command buffer
+ * (both include some extra chars)
+ */
+#define OS_TEST_SHELL_ECHO_BUFFER_SIZE (sizeof(OS_TEST_SHELL_STRING) + OS_TEST_SHELL_MAX_EXTRA_CHARS)
+#define OS_TEST_SHELL_CMD_BUFFER_SIZE  (sizeof(OS_TEST_SHELL_COMMAND) + OS_TEST_SHELL_ECHO_BUFFER_SIZE)
+
 /* *************************************** MAIN ************************************** */
 
 void TestOutputToFile(void)
 {
-    char      cmd[33];
+    char      cmd[OS_TEST_SHELL_CMD_BUFFER_SIZE + 1]; /* +1 char for term byte */
     char      filename[OS_MAX_PATH_LEN];
-    char      buffer[21];
-    char      copyofbuffer[21];
+    char      buffer[OS_TEST_SHELL_ECHO_BUFFER_SIZE + 1]; /* +1 char for term byte */
     size_t    size;
+    int32     filepos;
     int32     status;
     osal_id_t fd;
 
@@ -48,17 +69,12 @@ void TestOutputToFile(void)
     strncpy(filename, "/drive0/Filename1", sizeof(filename) - 1);
     filename[sizeof(filename) - 1] = 0;
 
-    strcpy(buffer, "ValueToEchoInTheFile");
-    strcpy(copyofbuffer, buffer); /* hold a copy of the buffer */
-
     /* Open In R/W mode */
     status = OS_OpenCreate(&fd, OS_TEST_SHELL_FILENAME, OS_FILE_FLAG_CREATE, OS_READ_WRITE);
     UtAssert_True(status >= OS_SUCCESS, "status after creat = %d", (int)status);
 
-    /* Write the string */
-    size = strlen(buffer);
-
-    snprintf(cmd, sizeof(cmd), "echo -n \"%s\"", buffer);
+    /* assemble command */
+    snprintf(cmd, sizeof(cmd), "%s \"%s\"", OS_TEST_SHELL_COMMAND, OS_TEST_SHELL_STRING);
 
     status = OS_ShellOutputToFile(cmd, fd);
     if (status == OS_ERR_NOT_IMPLEMENTED)
@@ -69,19 +85,43 @@ void TestOutputToFile(void)
     {
         UtAssert_True(status >= OS_SUCCESS, "status after shell output to file = %d", (int)status);
 
-        strcpy(buffer, "");
-
-        /* lseek back to the beginning of the file */
-        status = OS_lseek(fd, 0, 0);
-        UtAssert_True(status >= OS_SUCCESS, "status after lseek = %d", (int)status);
-
-        /*Read what we wrote to the file */
-        status = OS_read(fd, (void *)buffer, size);
-        UtAssert_True(status == size, "status after read = %d size = %lu", (int)status, (unsigned long)size);
-        if (status >= OS_SUCCESS)
+        /* output content should be at least this size */
+        size = sizeof(OS_TEST_SHELL_STRING) - 1;
+
+        /* Use lseek to determine size of the file */
+        filepos = OS_lseek(fd, 0, OS_SEEK_END);
+        UtAssert_True(filepos >= size, "size of output file=%d, echoed string len=%lu", (int)filepos,
+                      (unsigned long)size);
+
+        /*
+         * Different shells vary in how the echoed output actually appears in the file.
+         *
+         * Depending on config it may echo the command itself in addition to the output,
+         * and there may be whitespace/newlines that should be ignored.
+         *
+         * Either way the content should appear toward the _end_ of the file.
+         */
+        if (filepos < OS_TEST_SHELL_ECHO_BUFFER_SIZE)
         {
-            UtAssert_True(strcmp(buffer, copyofbuffer) == 0, "Read: %s, Written: %s", buffer, copyofbuffer);
+            filepos = 0;
         }
+        else
+        {
+            filepos -= OS_TEST_SHELL_ECHO_BUFFER_SIZE;
+        }
+
+        status = OS_lseek(fd, filepos, OS_SEEK_SET);
+        UtAssert_True(status == filepos, "lseek to position %d, result=%d", (int)filepos, (int)status);
+
+        /* Read what we wrote to the file */
+        /* By memset() first and reading one byte less than the buffer, the result is ensured to be terminated */
+        memset(buffer, 0, sizeof(buffer));
+        status = OS_read(fd, buffer, sizeof(buffer) - 1);
+        UtAssert_True(status >= size, "status after read = %d, min valid size = %lu", (int)status, (unsigned long)size);
+
+        /* The test should pass if the expected string is anywhere in the buffer */
+        UtAssert_True(strstr(buffer, OS_TEST_SHELL_STRING) != NULL, "Read: \'%s\', Expected: \'%s\'", buffer,
+                      OS_TEST_SHELL_STRING);
     }
 
     /* close the file */