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Diffstat (limited to 'lib/isc/dir.c')
| -rw-r--r-- | lib/isc/dir.c | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/lib/isc/dir.c b/lib/isc/dir.c new file mode 100644 index 0000000..b7eabe9 --- /dev/null +++ b/lib/isc/dir.c @@ -0,0 +1,268 @@ +/* + * Copyright (C) Internet Systems Consortium, Inc. ("ISC") + * + * SPDX-License-Identifier: MPL-2.0 + * + * 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 https://mozilla.org/MPL/2.0/. + * + * See the COPYRIGHT file distributed with this work for additional + * information regarding copyright ownership. + */ + +/*! \file */ + +#include <ctype.h> +#include <errno.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <unistd.h> + +#include <isc/dir.h> +#include <isc/magic.h> +#include <isc/netdb.h> +#include <isc/print.h> +#include <isc/string.h> +#include <isc/util.h> + +#include "errno2result.h" + +#define ISC_DIR_MAGIC ISC_MAGIC('D', 'I', 'R', '*') +#define VALID_DIR(dir) ISC_MAGIC_VALID(dir, ISC_DIR_MAGIC) + +void +isc_dir_init(isc_dir_t *dir) { + REQUIRE(dir != NULL); + + dir->entry.name[0] = '\0'; + dir->entry.length = 0; + + dir->handle = NULL; + + dir->magic = ISC_DIR_MAGIC; +} + +/*! + * \brief Allocate workspace and open directory stream. If either one fails, + * NULL will be returned. + */ +isc_result_t +isc_dir_open(isc_dir_t *dir, const char *dirname) { + char *p; + isc_result_t result = ISC_R_SUCCESS; + + REQUIRE(VALID_DIR(dir)); + REQUIRE(dirname != NULL); + + /* + * Copy directory name. Need to have enough space for the name, + * a possible path separator, the wildcard, and the final NUL. + */ + if (strlen(dirname) + 3 > sizeof(dir->dirname)) { + /* XXXDCL ? */ + return (ISC_R_NOSPACE); + } + strlcpy(dir->dirname, dirname, sizeof(dir->dirname)); + + /* + * Append path separator, if needed, and "*". + */ + p = dir->dirname + strlen(dir->dirname); + if (dir->dirname < p && *(p - 1) != '/') { + *p++ = '/'; + } + *p++ = '*'; + *p = '\0'; + + /* + * Open stream. + */ + dir->handle = opendir(dirname); + + if (dir->handle == NULL) { + return (isc__errno2result(errno)); + } + + return (result); +} + +/*! + * \brief Return previously retrieved file or get next one. + * + * Unix's dirent has + * separate open and read functions, but the Win32 and DOS interfaces open + * the dir stream and reads the first file in one operation. + */ +isc_result_t +isc_dir_read(isc_dir_t *dir) { + struct dirent *entry; + + REQUIRE(VALID_DIR(dir) && dir->handle != NULL); + + /* + * Fetch next file in directory. + */ + entry = readdir(dir->handle); + + if (entry == NULL) { + return (ISC_R_NOMORE); + } + + /* + * Make sure that the space for the name is long enough. + */ + if (sizeof(dir->entry.name) <= strlen(entry->d_name)) { + return (ISC_R_UNEXPECTED); + } + + strlcpy(dir->entry.name, entry->d_name, sizeof(dir->entry.name)); + + /* + * Some dirents have d_namlen, but it is not portable. + */ + dir->entry.length = strlen(entry->d_name); + + return (ISC_R_SUCCESS); +} + +/*! + * \brief Close directory stream. + */ +void +isc_dir_close(isc_dir_t *dir) { + REQUIRE(VALID_DIR(dir) && dir->handle != NULL); + + (void)closedir(dir->handle); + dir->handle = NULL; +} + +/*! + * \brief Reposition directory stream at start. + */ +isc_result_t +isc_dir_reset(isc_dir_t *dir) { + REQUIRE(VALID_DIR(dir) && dir->handle != NULL); + + rewinddir(dir->handle); + + return (ISC_R_SUCCESS); +} + +isc_result_t +isc_dir_chdir(const char *dirname) { + /*! + * \brief Change the current directory to 'dirname'. + */ + + REQUIRE(dirname != NULL); + + if (chdir(dirname) < 0) { + return (isc__errno2result(errno)); + } + + return (ISC_R_SUCCESS); +} + +isc_result_t +isc_dir_chroot(const char *dirname) { +#ifdef HAVE_CHROOT + void *tmp; +#endif /* ifdef HAVE_CHROOT */ + + REQUIRE(dirname != NULL); + +#ifdef HAVE_CHROOT + /* + * Try to use getservbyname and getprotobyname before chroot. + * If WKS records are used in a zone under chroot, Name Service Switch + * may fail to load library in chroot. + * Do not report errors if it fails, we do not need any result now. + */ + tmp = getprotobyname("udp"); + if (tmp != NULL) { + (void)getservbyname("domain", "udp"); + } + + if (chroot(dirname) < 0 || chdir("/") < 0) { + return (isc__errno2result(errno)); + } + + return (ISC_R_SUCCESS); +#else /* ifdef HAVE_CHROOT */ + return (ISC_R_NOTIMPLEMENTED); +#endif /* ifdef HAVE_CHROOT */ +} + +isc_result_t +isc_dir_createunique(char *templet) { + isc_result_t result; + char *x; + char *p; + int i; + int pid; + + REQUIRE(templet != NULL); + + /*! + * \brief mkdtemp is not portable, so this emulates it. + */ + + pid = getpid(); + + /* + * Replace trailing Xs with the process-id, zero-filled. + */ + for (x = templet + strlen(templet) - 1; *x == 'X' && x >= templet; + x--, pid /= 10) + { + *x = pid % 10 + '0'; + } + + x++; /* Set x to start of ex-Xs. */ + + do { + i = mkdir(templet, 0700); + if (i == 0 || errno != EEXIST) { + break; + } + + /* + * The BSD algorithm. + */ + p = x; + while (*p != '\0') { + if (isdigit((unsigned char)*p)) { + *p = 'a'; + } else if (*p != 'z') { + ++*p; + } else { + /* + * Reset character and move to next. + */ + *p++ = 'a'; + continue; + } + + break; + } + + if (*p == '\0') { + /* + * Tried all combinations. errno should already + * be EEXIST, but ensure it is anyway for + * isc__errno2result(). + */ + errno = EEXIST; + break; + } + } while (1); + + if (i == -1) { + result = isc__errno2result(errno); + } else { + result = ISC_R_SUCCESS; + } + + return (result); +} |