/*	$NetBSD: util.c,v 1.78 2021/12/15 12:58:01 rillig Exp $	*/

/*
 * Missing stuff from OS's
 */
#if defined(__MINT__) || defined(__linux__)
#include <signal.h>
#endif

#include <sys/param.h>

#include <errno.h>
#include <time.h>
#include <signal.h>

#include "make.h"

MAKE_RCSID("$NetBSD: util.c,v 1.78 2021/12/15 12:58:01 rillig Exp $");

#if !defined(MAKE_NATIVE) && !defined(HAVE_STRERROR)
extern int errno, sys_nerr;
extern char *sys_errlist[];

char *
strerror(int e)
{
	static char buf[100];
	if (e < 0 || e >= sys_nerr) {
		snprintf(buf, sizeof buf, "Unknown error %d", e);
		return buf;
	} else
		return sys_errlist[e];
}
#endif

#if !defined(MAKE_NATIVE) && !defined(HAVE_SETENV)
extern char **environ;

static char *
findenv(const char *name, int *offset)
{
	size_t i, len;
	char *p, *q;

	len = strlen(name);
	for (i = 0; (q = environ[i]); i++) {
		p = strchr(q, '=');
		if (p == NULL || p - q != len)
			continue;
		if (strncmp(name, q, len) == 0) {
			*offset = i;
			return q + len + 1;
		}
	}
	*offset = i;
	return NULL;
}

char *
getenv(const char *name)
{
	int offset;

	return findenv(name, &offset);
}

int
unsetenv(const char *name)
{
	char **p;
	int offset;

	if (name == NULL || *name == '\0' || strchr(name, '=') != NULL) {
		errno = EINVAL;
		return -1;
	}

	while (findenv(name, &offset)) {	/* if set multiple times */
		for (p = &environ[offset];; p++)
			if (!(*p = *(p + 1)))
				break;
	}
	return 0;
}

int
setenv(const char *name, const char *value, int rewrite)
{
	char *c, **newenv;
	const char *cc;
	size_t l_value, size;
	int offset;

	if (name == NULL || value == NULL) {
		errno = EINVAL;
		return -1;
	}

	if (*value == '=')	/* no `=' in value */
		value++;
	l_value = strlen(value);

	/* find if already exists */
	if ((c = findenv(name, &offset))) {
		if (!rewrite)
			return 0;
		if (strlen(c) >= l_value)	/* old larger; copy over */
			goto copy;
	} else {					/* create new slot */
		size = sizeof(char *) * (offset + 2);
		if (savedEnv == environ) {		/* just increase size */
			if ((newenv = realloc(savedEnv, size)) == NULL)
				return -1;
			savedEnv = newenv;
		} else {				/* get new space */
			/*
			 * We don't free here because we don't know if
			 * the first allocation is valid on all OS's
			 */
			if ((savedEnv = malloc(size)) == NULL)
				return -1;
			(void)memcpy(savedEnv, environ, size - sizeof(char *));
		}
		environ = savedEnv;
		environ[offset + 1] = NULL;
	}
	for (cc = name; *cc && *cc != '='; cc++)	/* no `=' in name */
		continue;
	size = cc - name;
	/* name + `=' + value */
	if ((environ[offset] = malloc(size + l_value + 2)) == NULL)
		return -1;
	c = environ[offset];
	(void)memcpy(c, name, size);
	c += size;
	*c++ = '=';
copy:
	(void)memcpy(c, value, l_value + 1);
	return 0;
}

#ifdef TEST
int
main(int argc, char *argv[])
{
	setenv(argv[1], argv[2], 0);
	printf("%s\n", getenv(argv[1]));
	unsetenv(argv[1]);
	printf("%s\n", getenv(argv[1]));
	return 0;
}
#endif

#endif

#if defined(__hpux__) || defined(__hpux)
/*
 * strrcpy():
 *	Like strcpy, going backwards and returning the new pointer
 */
static char *
strrcpy(char *ptr, char *str)
{
	int len = strlen(str);

	while (len != 0)
		*--ptr = str[--len];

	return ptr;
}

char *sys_siglist[] = {
	"Signal 0",
	"Hangup",			/* SIGHUP    */
	"Interrupt",			/* SIGINT    */
	"Quit",				/* SIGQUIT   */
	"Illegal instruction",		/* SIGILL    */
	"Trace/BPT trap",		/* SIGTRAP   */
	"IOT trap",			/* SIGIOT    */
	"EMT trap",			/* SIGEMT    */
	"Floating point exception",	/* SIGFPE    */
	"Killed",			/* SIGKILL   */
	"Bus error",			/* SIGBUS    */
	"Segmentation fault",		/* SIGSEGV   */
	"Bad system call",		/* SIGSYS    */
	"Broken pipe",			/* SIGPIPE   */
	"Alarm clock",			/* SIGALRM   */
	"Terminated",			/* SIGTERM   */
	"User defined signal 1",	/* SIGUSR1   */
	"User defined signal 2",	/* SIGUSR2   */
	"Child exited",			/* SIGCLD    */
	"Power-fail restart",		/* SIGPWR    */
	"Virtual timer expired",	/* SIGVTALRM */
	"Profiling timer expired",	/* SIGPROF   */
	"I/O possible",			/* SIGIO     */
	"Window size changes",		/* SIGWINDOW */
	"Stopped (signal)",		/* SIGSTOP   */
	"Stopped",			/* SIGTSTP   */
	"Continued",			/* SIGCONT   */
	"Stopped (tty input)",		/* SIGTTIN   */
	"Stopped (tty output)",		/* SIGTTOU   */
	"Urgent I/O condition",		/* SIGURG    */
	"Remote lock lost (NFS)",	/* SIGLOST   */
	"Signal 31",			/* reserved  */
	"DIL signal"			/* SIGDIL    */
};
#endif /* __hpux__ || __hpux */

#if defined(__hpux__) || defined(__hpux)
#include <sys/types.h>
#include <sys/syscall.h>
#include <sys/signal.h>
#include <sys/stat.h>
#include <dirent.h>
#include <sys/time.h>
#include <unistd.h>

int
killpg(int pid, int sig)
{
	return kill(-pid, sig);
}

#if !defined(BSD) && !defined(d_fileno)
# define d_fileno d_ino
#endif

#ifndef DEV_DEV_COMPARE
# define DEV_DEV_COMPARE(a, b) ((a) == (b))
#endif
#define ISDOT(c) ((c)[0] == '.' && (((c)[1] == '\0') || ((c)[1] == '/')))
#define ISDOTDOT(c) ((c)[0] == '.' && ISDOT(&((c)[1])))

char *
getwd(char *pathname)
{
    DIR    *dp;
    struct dirent *d;
    extern int errno;

    struct stat st_root, st_cur, st_next, st_dotdot;
    char    pathbuf[MAXPATHLEN], nextpathbuf[MAXPATHLEN * 2];
    char   *pathptr, *nextpathptr, *cur_name_add;

    /* find the inode of root */
    if (stat("/", &st_root) == -1) {
	(void)sprintf(pathname,
			"getwd: Cannot stat \"/\" (%s)", strerror(errno));
	return NULL;
    }
    pathbuf[MAXPATHLEN - 1] = '\0';
    pathptr = &pathbuf[MAXPATHLEN - 1];
    nextpathbuf[MAXPATHLEN - 1] = '\0';
    cur_name_add = nextpathptr = &nextpathbuf[MAXPATHLEN - 1];

    /* find the inode of the current directory */
    if (lstat(".", &st_cur) == -1) {
	(void)sprintf(pathname,
			"getwd: Cannot stat \".\" (%s)", strerror(errno));
	return NULL;
    }
    nextpathptr = strrcpy(nextpathptr, "../");

    /* Descend to root */
    for (;;) {

	/* look if we found root yet */
	if (st_cur.st_ino == st_root.st_ino &&
	    DEV_DEV_COMPARE(st_cur.st_dev, st_root.st_dev)) {
	    (void)strcpy(pathname, *pathptr != '/' ? "/" : pathptr);
	    return pathname;
	}

	/* open the parent directory */
	if (stat(nextpathptr, &st_dotdot) == -1) {
	    (void)sprintf(pathname,
			    "getwd: Cannot stat directory \"%s\" (%s)",
			    nextpathptr, strerror(errno));
	    return NULL;
	}
	if ((dp = opendir(nextpathptr)) == NULL) {
	    (void)sprintf(pathname,
			    "getwd: Cannot open directory \"%s\" (%s)",
			    nextpathptr, strerror(errno));
	    return NULL;
	}

	/* look in the parent for the entry with the same inode */
	if (DEV_DEV_COMPARE(st_dotdot.st_dev, st_cur.st_dev)) {
	    /* Parent has same device. No need to stat every member */
	    for (d = readdir(dp); d != NULL; d = readdir(dp))
		if (d->d_fileno == st_cur.st_ino)
		    break;
	} else {
	    /*
	     * Parent has a different device. This is a mount point so we
	     * need to stat every member
	     */
	    for (d = readdir(dp); d != NULL; d = readdir(dp)) {
		if (ISDOT(d->d_name) || ISDOTDOT(d->d_name))
		    continue;
		(void)strcpy(cur_name_add, d->d_name);
		if (lstat(nextpathptr, &st_next) == -1) {
		    (void)sprintf(pathname,
			"getwd: Cannot stat \"%s\" (%s)",
			d->d_name, strerror(errno));
		    (void)closedir(dp);
		    return NULL;
		}
		/* check if we found it yet */
		if (st_next.st_ino == st_cur.st_ino &&
		    DEV_DEV_COMPARE(st_next.st_dev, st_cur.st_dev))
		    break;
	    }
	}
	if (d == NULL) {
	    (void)sprintf(pathname,
		"getwd: Cannot find \".\" in \"..\"");
	    (void)closedir(dp);
	    return NULL;
	}
	st_cur = st_dotdot;
	pathptr = strrcpy(pathptr, d->d_name);
	pathptr = strrcpy(pathptr, "/");
	nextpathptr = strrcpy(nextpathptr, "../");
	(void)closedir(dp);
	*cur_name_add = '\0';
    }
} /* end getwd */
#endif /* __hpux */

/* force posix signals */
SignalProc
bmake_signal(int s, SignalProc a)
{
	struct sigaction sa, osa;

	sa.sa_handler = a;
	sigemptyset(&sa.sa_mask);
	sa.sa_flags = SA_RESTART;

	if (sigaction(s, &sa, &osa) == -1)
		return SIG_ERR;
	else
		return osa.sa_handler;
}

#if !defined(MAKE_NATIVE) && !defined(HAVE_VSNPRINTF)
#include <stdarg.h>

#if !defined(__osf__)
#ifdef _IOSTRG
#define STRFLAG	(_IOSTRG|_IOWRT)	/* no _IOWRT: avoid stdio bug */
#else
#if 0
#define STRFLAG	(_IOREAD)		/* XXX: Assume svr4 stdio */
#endif
#endif /* _IOSTRG */
#endif /* __osf__ */

int
vsnprintf(char *s, size_t n, const char *fmt, va_list args)
{
#ifdef STRFLAG
	FILE fakebuf;

	fakebuf._flag = STRFLAG;
	/*
	 * Some os's are char * _ptr, others are unsigned char *_ptr...
	 * We cast to void * to make everyone happy.
	 */
	fakebuf._ptr = (void *)s;
	fakebuf._cnt = n - 1;
	fakebuf._file = -1;
	_doprnt(fmt, args, &fakebuf);
	fakebuf._cnt++;
	putc('\0', &fakebuf);
	if (fakebuf._cnt < 0)
		fakebuf._cnt = 0;
	return n - fakebuf._cnt - 1;
#else
	::: "error: vsnprintf must be available";
#endif
}

int
snprintf(char *s, size_t n, const char *fmt, ...)
{
	va_list ap;
	int rv;

	va_start(ap, fmt);
	rv = vsnprintf(s, n, fmt, ap);
	va_end(ap);
	return rv;
}

#endif