src/relpipe-in-fstab.cpp
branchv_0
changeset 9 c0b16e4bd773
parent 8 21b14ec0bc60
child 19 3cc1b9be97bc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/relpipe-in-fstab.cpp	Sun Dec 09 18:23:25 2018 +0100
@@ -0,0 +1,125 @@
+/**
+ * Relational pipes
+ * Copyright © 2018 František Kučera (Frantovo.cz, GlobalCode.info)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <cstdlib>
+#include <fstream>
+#include <memory>
+#include <regex>
+#include <algorithm>
+#include <unistd.h>
+
+#include <relpipe/writer/RelationalWriter.h>
+#include <relpipe/writer/RelpipeWriterException.h>
+#include <relpipe/writer/Factory.h>
+#include <relpipe/writer/TypeId.h>
+
+#include <relpipe/cli/CLI.h>
+
+using namespace relpipe::cli;
+using namespace relpipe::writer;
+
+/**
+ * see https://hg.frantovo.cz/sql-api/file/tip/prototyp/prototyp.sql#l49
+ */
+void processDataStream(ostream &output, istream* input) {
+	wregex devicePattern = wregex(L"(LABEL|UUID)=(.*)");
+	wregex linePattern = wregex(L"^([^\\s#]+)\\s+([^\\s]+)\\s+([^\\s]+)\\s+([^\\s]+)\\s+(\\d+)\\s+(\\d+)\\s*$");
+	wstring_convert < codecvt_utf8<wchar_t>> convertor; // TODO: support also other encodings.
+
+	std::shared_ptr<RelationalWriter> writer(Factory::create(output));
+
+	writer->startRelation(L"fstab",{
+		{L"scheme", TypeId::STRING},
+		{L"device", TypeId::STRING},
+		{L"mount_point", TypeId::STRING},
+		{L"type", TypeId::STRING},
+		// {L"types", TypeId::STRING}, // TODO: array
+		{L"options", TypeId::STRING}, // TODO: array
+		{L"dump", TypeId::INTEGER},
+		{L"pass", TypeId::INTEGER}
+	}, true);
+
+	string lineBytes;
+	while (getline(*input, lineBytes)) {
+
+		wstring line = convertor.from_bytes(lineBytes);
+		wsmatch lineMatch;
+		if (regex_search(line, lineMatch, linePattern) && lineMatch.size() > 0) {
+			int g = 1;
+			wstring device = lineMatch[g++];
+			wstring mountPoint = lineMatch[g++];
+			wstring type = lineMatch[g++];
+			wstring options = lineMatch[g++];
+			wstring dump = lineMatch[g++];
+			wstring pass = lineMatch[g++];
+
+			wsmatch deviceMatch;
+			if (regex_search(device, deviceMatch, devicePattern)) {
+				writer->writeAttribute(deviceMatch[1]);
+				writer->writeAttribute(deviceMatch[2]);
+			} else {
+				writer->writeAttribute(L""); // TODO: null (requires bitmap)
+				writer->writeAttribute(device);
+			}
+
+			if (mountPoint == L"none") mountPoint = L""; // TODO: null (requires bitmap)
+			writer->writeAttribute(mountPoint);
+			writer->writeAttribute(type);
+			writer->writeAttribute(options);
+			writer->writeAttribute(dump);
+			writer->writeAttribute(pass);
+		}
+	}
+
+}
+
+int main(int argc, char** argv) {
+	setlocale(LC_ALL, "");
+	CLI::untieStdIO();
+	//CLI cli(argc, argv);
+
+	int resultCode = CLI::EXIT_CODE_UNEXPECTED_ERROR;
+
+	try {
+		if (isatty(fileno(stdin))) {
+			/**
+			 * Our program is executed on TTY without input stream redirection → read from default file location.
+			 * e.g. $ relpipe-in-fstab | …
+			 * (we don't expect that user is writing the content of fstab by hand on the terminal)
+			 */
+			ifstream s("/etc/fstab");
+			processDataStream(cout, &s);
+		} else {
+			/**
+			 * Input stream comes from a file or is piped from other command → read it instead of default file.
+			 * e.g. $ cat /etc/fstab | grep '/mnt/' | relpipe-in-fstab | …
+			 * or $ relpipe-in-fstab < /etc/fstab | … # without UUoC
+			 * or $ ssh example.com cat /etc/fstab | relpipe-in-fstab | …
+			 * or $ cat | relpipe-in-fstab | … # user writes the fstab content by hand
+			 */
+			processDataStream(cout, &cin);
+		}
+		resultCode = CLI::EXIT_CODE_SUCCESS;
+
+	} catch (RelpipeWriterException e) {
+		fwprintf(stderr, L"Caught Writer exception: %ls\n", e.getMessge().c_str());
+		fwprintf(stderr, L"Debug: Input stream: eof=%ls, lastRead=%d\n", (cin.eof() ? L"true" : L"false"), cin.gcount());
+		resultCode = CLI::EXIT_CODE_DATA_ERROR;
+	}
+
+	return resultCode;
+}