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Diffstat (limited to 'usr.bin/more/os.c')
| -rw-r--r-- | usr.bin/more/os.c | 283 |
1 files changed, 283 insertions, 0 deletions
diff --git a/usr.bin/more/os.c b/usr.bin/more/os.c new file mode 100644 index 0000000..75b7a6e --- /dev/null +++ b/usr.bin/more/os.c @@ -0,0 +1,283 @@ +/* + * Copyright (c) 1988 Mark Nudleman + * Copyright (c) 1988, 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. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 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. + */ + +#ifndef lint +static char sccsid[] = "@(#)os.c 8.1 (Berkeley) 6/6/93"; +#endif /* not lint */ + +/* + * Operating system dependent routines. + * + * Most of the stuff in here is based on Unix, but an attempt + * has been made to make things work on other operating systems. + * This will sometimes result in a loss of functionality, unless + * someone rewrites code specifically for the new operating system. + * + * The makefile provides defines to decide whether various + * Unix features are present. + */ + +#include <sys/param.h> +#include <sys/stat.h> +#include <sys/file.h> +#include <signal.h> +#include <setjmp.h> +#include <stdio.h> +#include <less.h> +#include "pathnames.h" + +int reading; + +extern int screen_trashed; + +static jmp_buf read_label; + +/* + * Pass the specified command to a shell to be executed. + * Like plain "system()", but handles resetting terminal modes, etc. + */ +lsystem(cmd) + char *cmd; +{ + int inp; + char cmdbuf[256]; + char *shell, *getenv(); + + /* + * Print the command which is to be executed, + * unless the command starts with a "-". + */ + if (cmd[0] == '-') + cmd++; + else + { + lower_left(); + clear_eol(); + putstr("!"); + putstr(cmd); + putstr("\n"); + } + + /* + * De-initialize the terminal and take out of raw mode. + */ + deinit(); + flush(); + raw_mode(0); + + /* + * Restore signals to their defaults. + */ + init_signals(0); + + /* + * Force standard input to be the terminal, "/dev/tty", + * even if less's standard input is coming from a pipe. + */ + inp = dup(0); + (void)close(0); + if (open(_PATH_TTY, O_RDONLY, 0) < 0) + (void)dup(inp); + + /* + * Pass the command to the system to be executed. + * If we have a SHELL environment variable, use + * <$SHELL -c "command"> instead of just <command>. + * If the command is empty, just invoke a shell. + */ + if ((shell = getenv("SHELL")) != NULL && *shell != '\0') + { + if (*cmd == '\0') + cmd = shell; + else + { + (void)sprintf(cmdbuf, "%s -c \"%s\"", shell, cmd); + cmd = cmdbuf; + } + } + if (*cmd == '\0') + cmd = "sh"; + + (void)system(cmd); + + /* + * Restore standard input, reset signals, raw mode, etc. + */ + (void)close(0); + (void)dup(inp); + (void)close(inp); + + init_signals(1); + raw_mode(1); + init(); + screen_trashed = 1; +#if defined(SIGWINCH) || defined(SIGWIND) + /* + * Since we were ignoring window change signals while we executed + * the system command, we must assume the window changed. + */ + winch(); +#endif +} + +/* + * Like read() system call, but is deliberately interruptable. + * A call to intread() from a signal handler will interrupt + * any pending iread(). + */ +iread(fd, buf, len) + int fd; + char *buf; + int len; +{ + register int n; + + if (setjmp(read_label)) + /* + * We jumped here from intread. + */ + return (READ_INTR); + + flush(); + reading = 1; + n = read(fd, buf, len); + reading = 0; + if (n < 0) + return (-1); + return (n); +} + +intread() +{ + (void)sigsetmask(0L); + longjmp(read_label, 1); +} + +/* + * Expand a filename, substituting any environment variables, etc. + * The implementation of this is necessarily very operating system + * dependent. This implementation is unabashedly only for Unix systems. + */ +FILE *popen(); + +char * +glob(filename) + char *filename; +{ + FILE *f; + char *p; + int ch; + char *cmd, *malloc(), *getenv(); + static char buffer[MAXPATHLEN]; + + if (filename[0] == '#') + return (filename); + + /* + * We get the shell to expand the filename for us by passing + * an "echo" command to the shell and reading its output. + */ + p = getenv("SHELL"); + if (p == NULL || *p == '\0') + { + /* + * Read the output of <echo filename>. + */ + cmd = malloc((u_int)(strlen(filename)+8)); + if (cmd == NULL) + return (filename); + (void)sprintf(cmd, "echo \"%s\"", filename); + } else + { + /* + * Read the output of <$SHELL -c "echo filename">. + */ + cmd = malloc((u_int)(strlen(p)+12)); + if (cmd == NULL) + return (filename); + (void)sprintf(cmd, "%s -c \"echo %s\"", p, filename); + } + + if ((f = popen(cmd, "r")) == NULL) + return (filename); + free(cmd); + + for (p = buffer; p < &buffer[sizeof(buffer)-1]; p++) + { + if ((ch = getc(f)) == '\n' || ch == EOF) + break; + *p = ch; + } + *p = '\0'; + (void)pclose(f); + return(buffer); +} + +char * +bad_file(filename, message, len) + char *filename, *message; + u_int len; +{ + extern int errno; + struct stat statbuf; + char *strcat(), *strerror(); + + if (stat(filename, &statbuf) < 0) { + (void)sprintf(message, "%s: %s", filename, strerror(errno)); + return(message); + } + if ((statbuf.st_mode & S_IFMT) == S_IFDIR) { + static char is_dir[] = " is a directory"; + + strtcpy(message, filename, (int)(len-sizeof(is_dir)-1)); + (void)strcat(message, is_dir); + return(message); + } + return((char *)NULL); +} + +/* + * Copy a string, truncating to the specified length if necessary. + * Unlike strncpy(), the resulting string is guaranteed to be null-terminated. + */ +strtcpy(to, from, len) + char *to, *from; + int len; +{ + char *strncpy(); + + (void)strncpy(to, from, (int)len); + to[len-1] = '\0'; +} + |
