1 files changed, 134 insertions, 0 deletions
diff --git a/nsprpub/tools/tail.c b/nsprpub/tools/tail.c
new file mode 100644
index 000000000..32c93ddfd
--- /dev/null
+++ b/nsprpub/tools/tail.c
@@ -0,0 +1,134 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "prio.h"
+#include "prprf.h"
+#include "prinit.h"
+#include "prthread.h"
+#include "prinrval.h"
+
+#include "plerror.h"
+#include "plgetopt.h"
+
+#include <stdlib.h>
+
+#define BUFFER_SIZE 500
+
+static PRFileDesc *out = NULL, *err = NULL;
+
+static void Help(void)
+{
+    PR_fprintf(err, "Usage: tail [-n <n>] [-f] [-h] <filename>\n");
+    PR_fprintf(err, "\t-t <n>	Dally time in milliseconds\n");
+    PR_fprintf(err, "\t-n <n>	Number of bytes before <eof>\n");
+    PR_fprintf(err, "\t-f   	Follow the <eof>\n");
+    PR_fprintf(err, "\t-h   	This message and nothing else\n");
+}  /* Help */
+
+PRIntn main(PRIntn argc, char **argv)
+{
+	PRIntn rv = 0;
+    PLOptStatus os;
+	PRStatus status;
+	PRFileDesc *file;
+	PRFileInfo fileInfo;
+	PRIntervalTime dally;
+	char buffer[BUFFER_SIZE];
+	PRBool follow = PR_FALSE;
+	const char *filename = NULL;
+	PRUint32 position = 0, seek = 0, time = 0;
+    PLOptState *opt = PL_CreateOptState(argc, argv, "hfn:");
+
+    out = PR_GetSpecialFD(PR_StandardOutput);
+    err = PR_GetSpecialFD(PR_StandardError);
+
+    while (PL_OPT_EOL != (os = PL_GetNextOpt(opt)))
+    {
+        if (PL_OPT_BAD == os) continue;
+        switch (opt->option)
+        {
+		case 0:  /* it's the filename */
+			filename = opt->value;
+			break;
+        case 'n':  /* bytes before end of file */
+            seek = atoi(opt->value);
+            break;
+        case 't':  /* dally time */
+            time = atoi(opt->value);
+            break;
+        case 'f':  /* follow the end of file */
+            follow = PR_TRUE;
+            break;
+        case 'h':  /* user wants some guidance */
+            Help();  /* so give him an earful */
+            return 2;  /* but not a lot else */
+            break;
+         default:
+            break;
+        }
+    }
+    PL_DestroyOptState(opt);
+
+	if (0 == time) time = 1000;
+	dally = PR_MillisecondsToInterval(time);
+
+    if (NULL == filename)
+    {
+        (void)PR_fprintf(out, "Input file not specified\n");
+        rv = 1; goto done;
+    }
+	file = PR_Open(filename, PR_RDONLY, 0);
+	if (NULL == file)
+	{
+		PL_FPrintError(err, "File cannot be opened for reading");
+		return 1;
+	}
+
+	status = PR_GetOpenFileInfo(file, &fileInfo);
+	if (PR_FAILURE == status)
+	{
+		PL_FPrintError(err, "Cannot acquire status of file");
+		rv = 1; goto done;
+	}
+	if (seek > 0)
+	{
+	    if (seek > fileInfo.size) seek = 0;
+		position = PR_Seek(file, (fileInfo.size - seek), PR_SEEK_SET);
+		if (-1 == (PRInt32)position)
+			PL_FPrintError(err, "Cannot seek to starting position");
+	}
+
+	do
+	{
+		while (position < fileInfo.size)
+		{
+			PRInt32 read, bytes = fileInfo.size - position;
+			if (bytes > sizeof(buffer)) bytes = sizeof(buffer);
+			read = PR_Read(file, buffer, bytes);
+			if (read != bytes)
+				PL_FPrintError(err, "Cannot read to eof");
+			position += read;
+			PR_Write(out, buffer, read);
+		}
+
+		if (follow)
+		{
+			PR_Sleep(dally);
+			status = PR_GetOpenFileInfo(file, &fileInfo);
+			if (PR_FAILURE == status)
+			{
+				PL_FPrintError(err, "Cannot acquire status of file");
+				rv = 1; goto done;
+			}
+		}
+	} while (follow);
+
+done:
+	PR_Close(file);
+
+	return rv;
+}  /* main */
+
+/* tail.c */