coreutils

realpath: Add realpath utility

Diffstat

4 files changed, 135 insertions, 0 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index aba9e71..ba773b5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -22,6 +22,7 @@ ADD_EXECUTABLE(mkdir    ${CMAKE_SOURCE_DIR}/src/mkdir.c)
 ADD_EXECUTABLE(nice     ${CMAKE_SOURCE_DIR}/src/nice.c)
 ADD_EXECUTABLE(pwd      ${CMAKE_SOURCE_DIR}/src/pwd.c)
 ADD_EXECUTABLE(rand     ${CMAKE_SOURCE_DIR}/src/rand.c)
+ADD_EXECUTABLE(realpath ${CMAKE_SOURCE_DIR}/src/realpath.c)
 ADD_EXECUTABLE(rmdir    ${CMAKE_SOURCE_DIR}/src/rmdir.c)
 ADD_EXECUTABLE(sleep    ${CMAKE_SOURCE_DIR}/src/sleep.c)
 ADD_EXECUTABLE(sync     ${CMAKE_SOURCE_DIR}/src/sync.c)
diff --git a/README.md b/README.md
index 452027b..36c7d4f 100644
--- a/README.md
+++ b/README.md
@@ -21,6 +21,7 @@ UNIX-like systems.
 | nice             | Execute with an altered nice value       | POSIX    |
 | pwd              | Print working directory                  | POSIX    |
 | rand             | Generate random string                   |          |
+| realpath         | Resolve an absolute pathname             |          |
 | rmdir            | Remove directories                       | POSIX    |
 | sleep            | Suspend execution for an interval        | POSIX    |
 | sync             | Synchronise file system caches to disk   |          |
diff --git a/man/realpath.1 b/man/realpath.1
new file mode 100644
index 0000000..c4e2c39
--- /dev/null
+++ b/man/realpath.1
@@ -0,0 +1,35 @@
+.TH REALPATH 1 2020-06-27 "OMKOV coreutils" "General Commands Manual"
+.SH NAME
+realpath \(em resolve an absolute pathname
+.SH SYNOPSYS
+\fBrealpath\fR [\fIfile\fR...]
+.SH DESCRIPTION
+Resolve the absolute path for each input \fIfile\fR. If \fIfile\fR is
+unspecified, the path of the current working directory will be resolved.
+.SH OPTIONS
+The following options are supported:
+.TP
+.B --help
+Display help information.
+.TP
+.B --version
+Display version information.
+.SH OPERANDS
+The following operand is supported:
+.TP
+.I file
+A pathname of a file.
+.SH EXIT STATUS
+The following exit values will be returned:
+.TP
+\ 0
+Successful completion.
+.TP
+>0
+An error occurred.
+.SH COPYRIGHT
+.nf
+Copyright (C) 2020, Jakob Wakeling
+All rights reserved.
+OMKOV Permissive Licence (https://www.omkov.net/OLPE)
+.fi
diff --git a/src/realpath.c b/src/realpath.c
new file mode 100644
index 0000000..ff40e7c
--- /dev/null
+++ b/src/realpath.c
@@ -0,0 +1,98 @@
+// realpath.c, version 1.0.0
+// OMKOV coreutils realpath
+// Copyright (C) 2020, Jakob Wakeling
+// All rights reserved.
+
+/*
+OMKOV Permissive Licence, version 1.0
+
+Copyright (C) 2020, Jakob Wakeling
+All rights reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal with
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimers.
+* Redistributions in binary form must reproduce the above copyright notice, this
+  list of conditions and the following disclaimers in the documentation and/or
+  other materials provided with the distribution.
+* Neither the names of the copyright holders, nor the names of its contributors
+  may be used to endorse or promote products derived from this Software without
+  specific prior written permission.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE COPYRIGHT
+HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS WITH THE SOFTWARE.
+*/
+
+#include "error.h"
+#include "optget.h"
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static inline int rpath(const char *path);
+
+static void help(void);
+static void version(void);
+
+int main(int argc, char *argv[]) {
+	lop_t lops[] = {
+		{ "help",    ARG_NUL, 256 },
+		{ "version", ARG_NUL, 257 },
+		{ NULL, 0, 0 }
+	};
+	
+	opt_t opt = OPTGET_INIT; opt.str = ""; opt.lops = lops; int o;
+	while((o = optget(&opt, argv, 1)) != -1) switch (o) {
+	case 256: { help(); return 0; }
+	case 257: { version(); return 0; }
+	default: { return 1; }
+	}
+	
+	bool warned = false;
+	
+	if (opt.ind == argc) { rpath("."); }
+	else for (char **p = &argv[opt.ind]; *p; ++p) if (rpath(*p)) {
+		warn("%s: %s: %s\n", argv[0], *p, serrno); warned = true;
+	}
+	
+	return warned;
+}
+
+static inline int rpath(const char *file) {
+	char *path;
+	
+	if (!(path = realpath(file, NULL))) { return 1; }
+	fputs(path, stdout); fputc('\n', stdout);
+	
+	free(path); return 0;
+}
+
+static void help(void) {
+	puts("realpath - resolve an absolute pathname\n");
+	puts("usage: realpath [file...]\n");
+	puts("options:");
+	puts("  --help     Display help information");
+	puts("  --version  Display version information");
+	return;
+}
+
+static void version() {
+	puts("OMKOV coreutils realpath, version 1.0.0");
+	puts("Copyright (C) 2020, Jakob Wakeling");
+	puts("All rights reserved.");
+	puts("OMKOV Permissive Licence (https://www.omkov.net/OLPE)");
+	return;
+}