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Diffstat (limited to 'src/tools/xcode/realpath/realpath.c')
-rw-r--r-- | src/tools/xcode/realpath/realpath.c | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/src/tools/xcode/realpath/realpath.c b/src/tools/xcode/realpath/realpath.c new file mode 100644 index 0000000000..06addf38c7 --- /dev/null +++ b/src/tools/xcode/realpath/realpath.c @@ -0,0 +1,103 @@ +// Copyright 2015 Google Inc. All rights reserved. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +// realpath.c +// +// A simple implementation of realpath for Mac OS X. +// This implementation follows gnu/linux conventions and allows the last +// component to not exist: +// http://www.gnu.org/software/coreutils/manual/html_node/realpath-invocation.html +// Debian requires all components to exist. +// + +#include <errno.h> +#include <libgen.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +// Print a simple error message and exit. +static void PrintError(const char *argv[]) { + fprintf(stderr, "%s: %s\n", argv[1], strerror(errno)); + exit(1); +} + +// Concatenate two paths together adding a '/' if appropriate. +// Returned pointer is owned by client and should be freed. +static char *JoinPaths(const char *path1, const char* path2) { + size_t len1 = strlen(path1); + size_t len2 = strlen(path2); + // +1 for '/' and +1 for '\0' + size_t totalSize = len1 + 1 + len2 + 1; + char *outPath = malloc(totalSize); + if (outPath == NULL) { + return NULL; + } + strlcpy(outPath, path1, totalSize); + if (len1 > 0 && len2 > 0) { + if (path1[len1 - 1] != '/' && path2[0] != '/') { + strlcat(outPath, "/", totalSize); + } + } + strlcat(outPath, path2, totalSize); + return outPath; +} + +// Since this is a simple utility that quits immediately, we are not worrying +// about making the code more complex by freeing up any memory allocations. +int main(int argc, const char *argv[]) { + if (argc != 2) { + fprintf(stderr, "realpath <path>\n"); + return 1; + } + const char *path = argv[1]; + char *goodPath = realpath(path, NULL); + if (goodPath == NULL) { + if ((errno != ENOENT) || (strlen(path) == 0)) { + PrintError(argv); + } + + // If only the last element is missing, then call realpath on the parent + // dir and append the basename back onto it. + + // Technically the strdup is not required on Mac OS X, but this + // keeps things compatible with other basename/dirname implementations + // that do require a string they can modify. + char *dirCopy = strdup(path); + char *baseCopy = strdup(path); + if (dirCopy == NULL || baseCopy == NULL) { + PrintError(argv); + } + char *dir = dirname(dirCopy); + if (dir == NULL) { + PrintError(argv); + } + char *base = basename(baseCopy); + if (base == NULL) { + PrintError(argv); + } + char *realdir = realpath(dir, NULL); + if (realdir == NULL) { + PrintError(argv); + } + goodPath = JoinPaths(realdir, base); + if (goodPath == NULL) { + PrintError(argv); + } + } + fprintf(stdout, "%s\n", goodPath); + return 0; +} |