X-Git-Url: https://git.cworth.org/git?a=blobdiff_plain;f=thirdparty%2Fless%2Fos.c;fp=thirdparty%2Fless%2Fos.c;h=dbb52fe3b85f131cf435a50b08ed78a2e7596098;hb=70c3470408854526136adcf3705d1dc7e7189c0a;hp=0000000000000000000000000000000000000000;hpb=d3846c6fda2eb17ccd0402551be8b569ab2dbc5a;p=apitrace diff --git a/thirdparty/less/os.c b/thirdparty/less/os.c new file mode 100644 index 0000000..dbb52fe --- /dev/null +++ b/thirdparty/less/os.c @@ -0,0 +1,364 @@ +/* + * Copyright (C) 1984-2011 Mark Nudelman + * + * You may distribute under the terms of either the GNU General Public + * License or the Less License, as specified in the README file. + * + * For more information about less, or for information on how to + * contact the author, see the README file. + */ + + +/* + * 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 "less.h" +#include +#include +#if HAVE_TIME_H +#include +#endif +#if HAVE_ERRNO_H +#include +#endif +#if HAVE_VALUES_H +#include +#endif + +#if HAVE_TIME_T +#define time_type time_t +#else +#define time_type long +#endif + +/* + * BSD setjmp() saves (and longjmp() restores) the signal mask. + * This costs a system call or two per setjmp(), so if possible we clear the + * signal mask with sigsetmask(), and use _setjmp()/_longjmp() instead. + * On other systems, setjmp() doesn't affect the signal mask and so + * _setjmp() does not exist; we just use setjmp(). + */ +#if HAVE__SETJMP && HAVE_SIGSETMASK +#define SET_JUMP _setjmp +#define LONG_JUMP _longjmp +#else +#define SET_JUMP setjmp +#define LONG_JUMP longjmp +#endif + +public int reading; + +static jmp_buf read_label; + +extern int sigs; + +/* + * Like read() system call, but is deliberately interruptible. + * A call to intread() from a signal handler will interrupt + * any pending iread(). + */ + public int +iread(fd, buf, len) + int fd; + char *buf; + unsigned int len; +{ + register int n; + +start: +#if MSDOS_COMPILER==WIN32C + if (ABORT_SIGS()) + return (READ_INTR); +#else +#if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC + if (kbhit()) + { + int c; + + c = getch(); + if (c == '\003') + return (READ_INTR); + ungetch(c); + } +#endif +#endif + if (SET_JUMP(read_label)) + { + /* + * We jumped here from intread. + */ + reading = 0; +#if HAVE_SIGPROCMASK + { + sigset_t mask; + sigemptyset(&mask); + sigprocmask(SIG_SETMASK, &mask, NULL); + } +#else +#if HAVE_SIGSETMASK + sigsetmask(0); +#else +#ifdef _OSK + sigmask(~0); +#endif +#endif +#endif + return (READ_INTR); + } + + flush(); + reading = 1; +#if MSDOS_COMPILER==DJGPPC + if (isatty(fd)) + { + /* + * Don't try reading from a TTY until a character is + * available, because that makes some background programs + * believe DOS is busy in a way that prevents those + * programs from working while "less" waits. + */ + fd_set readfds; + + FD_ZERO(&readfds); + FD_SET(fd, &readfds); + if (select(fd+1, &readfds, 0, 0, 0) == -1) + return (-1); + } +#endif + n = read(fd, buf, len); +#if 1 + /* + * This is a kludge to workaround a problem on some systems + * where terminating a remote tty connection causes read() to + * start returning 0 forever, instead of -1. + */ + { + extern int ignore_eoi; + if (!ignore_eoi) + { + static int consecutive_nulls = 0; + if (n == 0) + consecutive_nulls++; + else + consecutive_nulls = 0; + if (consecutive_nulls > 20) + quit(QUIT_ERROR); + } + } +#endif + reading = 0; + if (n < 0) + { +#if HAVE_ERRNO + /* + * Certain values of errno indicate we should just retry the read. + */ +#if MUST_DEFINE_ERRNO + extern int errno; +#endif +#ifdef EINTR + if (errno == EINTR) + goto start; +#endif +#ifdef EAGAIN + if (errno == EAGAIN) + goto start; +#endif +#endif + return (-1); + } + return (n); +} + +/* + * Interrupt a pending iread(). + */ + public void +intread() +{ + LONG_JUMP(read_label, 1); +} + +/* + * Return the current time. + */ +#if HAVE_TIME + public long +get_time() +{ + time_type t; + + time(&t); + return (t); +} +#endif + + +#if !HAVE_STRERROR +/* + * Local version of strerror, if not available from the system. + */ + static char * +strerror(err) + int err; +{ +#if HAVE_SYS_ERRLIST + static char buf[16]; + extern char *sys_errlist[]; + extern int sys_nerr; + + if (err < sys_nerr) + return sys_errlist[err]; + sprintf(buf, "Error %d", err); + return buf; +#else + return ("cannot open"); +#endif +} +#endif + +/* + * errno_message: Return an error message based on the value of "errno". + */ + public char * +errno_message(filename) + char *filename; +{ + register char *p; + register char *m; + int len; +#if HAVE_ERRNO +#if MUST_DEFINE_ERRNO + extern int errno; +#endif + p = strerror(errno); +#else + p = "cannot open"; +#endif + len = strlen(filename) + strlen(p) + 3; + m = (char *) ecalloc(len, sizeof(char)); + SNPRINTF2(m, len, "%s: %s", filename, p); + return (m); +} + +/* #define HAVE_FLOAT 0 */ + + static POSITION +muldiv(val, num, den) + POSITION val, num, den; +{ +#if HAVE_FLOAT + double v = (((double) val) * num) / den; + return ((POSITION) (v + 0.5)); +#else + POSITION v = ((POSITION) val) * num; + + if (v / num == val) + /* No overflow */ + return (POSITION) (v / den); + else + /* Above calculation overflows; + * use a method that is less precise but won't overflow. */ + return (POSITION) (val / (den / num)); +#endif +} + +/* + * Return the ratio of two POSITIONS, as a percentage. + * {{ Assumes a POSITION is a long int. }} + */ + public int +percentage(num, den) + POSITION num, den; +{ + return (int) muldiv(num, (POSITION) 100, den); +} + +/* + * Return the specified percentage of a POSITION. + */ + public POSITION +percent_pos(pos, percent, fraction) + POSITION pos; + int percent; + long fraction; +{ + /* Change percent (parts per 100) to perden (parts per NUM_FRAC_DENOM). */ + POSITION perden = (percent * (NUM_FRAC_DENOM / 100)) + (fraction / 100); + + if (perden == 0) + return (0); + return (POSITION) muldiv(pos, perden, (POSITION) NUM_FRAC_DENOM); +} + +#if !HAVE_STRCHR +/* + * strchr is used by regexp.c. + */ + char * +strchr(s, c) + char *s; + int c; +{ + for ( ; *s != '\0'; s++) + if (*s == c) + return (s); + if (c == '\0') + return (s); + return (NULL); +} +#endif + +#if !HAVE_MEMCPY + VOID_POINTER +memcpy(dst, src, len) + VOID_POINTER dst; + VOID_POINTER src; + int len; +{ + char *dstp = (char *) dst; + char *srcp = (char *) src; + int i; + + for (i = 0; i < len; i++) + dstp[i] = srcp[i]; + return (dst); +} +#endif + +#ifdef _OSK_MWC32 + +/* + * This implements an ANSI-style intercept setup for Microware C 3.2 + */ + public int +os9_signal(type, handler) + int type; + RETSIGTYPE (*handler)(); +{ + intercept(handler); +} + +#include + + int +isatty(f) + int f; +{ + struct sgbuf sgbuf; + + if (_gs_opt(f, &sgbuf) < 0) + return -1; + return (sgbuf.sg_class == 0); +} + +#endif