diff options
Diffstat (limited to 'bin/echo/echo.c')
| -rw-r--r-- | bin/echo/echo.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/bin/echo/echo.c b/bin/echo/echo.c new file mode 100644 index 0000000..68ff581 --- /dev/null +++ b/bin/echo/echo.c @@ -0,0 +1,137 @@ +/*- + * Copyright (c) 1989, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#if 0 +#ifndef lint +static char const copyright[] = +"@(#) Copyright (c) 1989, 1993\n\ + The Regents of the University of California. All rights reserved.\n"; +#endif /* not lint */ + +#ifndef lint +static char sccsid[] = "@(#)echo.c 8.1 (Berkeley) 5/31/93"; +#endif /* not lint */ +#endif +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/types.h> +#include <sys/uio.h> + +#include <assert.h> +#include <errno.h> +#include <limits.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +/* + * Report an error and exit. + * Use it instead of err(3) to avoid linking-in stdio. + */ +static __dead2 void +errexit(const char *prog, const char *reason) +{ + char *errstr = strerror(errno); + write(STDERR_FILENO, prog, strlen(prog)); + write(STDERR_FILENO, ": ", 2); + write(STDERR_FILENO, reason, strlen(reason)); + write(STDERR_FILENO, ": ", 2); + write(STDERR_FILENO, errstr, strlen(errstr)); + write(STDERR_FILENO, "\n", 1); + exit(1); +} + +int +main(int argc, char *argv[]) +{ + int nflag; /* if not set, output a trailing newline. */ + int veclen; /* number of writev arguments. */ + struct iovec *iov, *vp; /* Elements to write, current element. */ + char space[] = " "; + char newline[] = "\n"; + char *progname = argv[0]; + + /* This utility may NOT do getopt(3) option parsing. */ + if (*++argv && !strcmp(*argv, "-n")) { + ++argv; + --argc; + nflag = 1; + } else + nflag = 0; + + veclen = (argc >= 2) ? (argc - 2) * 2 + 1 : 0; + + if ((vp = iov = malloc((veclen + 1) * sizeof(struct iovec))) == NULL) + errexit(progname, "malloc"); + + while (argv[0] != NULL) { + size_t len; + + len = strlen(argv[0]); + + /* + * If the next argument is NULL then this is this + * the last argument, therefore we need to check + * for a trailing \c. + */ + if (argv[1] == NULL) { + /* is there room for a '\c' and is there one? */ + if (len >= 2 && + argv[0][len - 2] == '\\' && + argv[0][len - 1] == 'c') { + /* chop it and set the no-newline flag. */ + len -= 2; + nflag = 1; + } + } + vp->iov_base = *argv; + vp++->iov_len = len; + if (*++argv) { + vp->iov_base = space; + vp++->iov_len = 1; + } + } + if (!nflag) { + veclen++; + vp->iov_base = newline; + vp++->iov_len = 1; + } + /* assert(veclen == (vp - iov)); */ + while (veclen) { + int nwrite; + + nwrite = (veclen > IOV_MAX) ? IOV_MAX : veclen; + if (writev(STDOUT_FILENO, iov, nwrite) == -1) + errexit(progname, "write"); + iov += nwrite; + veclen -= nwrite; + } + return 0; +} |
