Re: Porting git to HP NonStop

Brandon Casey [off-list ref] writes:

With two function-scope static, you can go like this:

die()
-> die_routine()
   -> xsomething()
      -> die_errno()
        -> die_routine()
           -> xsomethingelse()
              -> die() or die_errno()

Not that we probably care too deeply about, as at least we won't
infinitely recurse and die out of stack space.

On Wed, Aug 22, 2012 at 11:33 AM, Junio C Hamano [off-list ref] wrote:

Brandon Casey [off-list ref] writes:

quoted

Perhaps something like:

diff --git a/usage.c b/usage.c
index a2a6678..2d0ff35 100644
--- a/usage.c
+++ b/usage.c

@@ -80,8 +80,15 @@ void NORETURN usage(const char *err)

 void NORETURN die(const char *err, ...)
 {
+       static int dying;
        va_list params;

+       if (dying) {
+               fputs("fatal: recursion detected in die handler\n", stderr);
+               exit(128);
+       }
+       dying = 1;
+
        va_start(params, err);
        die_routine(err, params);
        va_end(params);

@@ -89,11 +96,18 @@ void NORETURN die(const char *err, ...)

 void NORETURN die_errno(const char *fmt, ...)
 {
+       static int dying;
        va_list params;
        char fmt_with_err[1024];
        char str_error[256], *err;
        int i, j;

+       if (dying) {
+               fputs("fatal: recursion detected in die handler\n", stderr);
+               exit(128);
+       }
+       dying = 1;
+
        err = strerror(errno);
        for (i = j = 0; err[i] && j < sizeof(str_error) - 1; ) {
                if ((str_error[j++] = err[i++]) != '%')

With two function-scope static, you can go like this:

die()
-> die_routine()
   -> xsomething()
      -> die_errno()
        -> die_routine()
           -> xsomethingelse()
              -> die() or die_errno()

Not that we probably care too deeply about, as at least we won't
infinitely recurse and die out of stack space.

Yeah, I noticed that, but didn't think it was important or likely.
But there's no reason not to make "dying" a global.

-Brandon

Hi folks

There another API missing on HP NonStop and that is setitimer(), used in progress.c and build/log.c
I do have a homebrewed implementation, on top of alarm(), it goes like this:

#include "../git-compat-util.h"
#undef getitimer
#undef setitimer


int
git_getitimer(int which, struct itimerval *value)
{
        int ret = 0;

        switch (which) {
                case ITIMER_REAL:
                        value->it_value.tv_usec = 0;
                        value->it_value.tv_sec = alarm(0);
                        ret = 0; /* if alarm() fails we get a SIGLIMIT */
                        break;
                case ITIMER_VIRTUAL: /* FALLTHRU */
                case ITIMER_PROF: errno = ENOTSUP; ret = -1; break;
                default: errno = EINVAL; ret = -1;
        }
        return ret;
}

int
git_setitimer(int which, const struct itimerval *value,
                        struct itimerval *ovalue)
{
        int ret = 0;

        if (!value
                || value->it_value.tv_usec < 0
                || value->it_value.tv_usec > 1000000
                || value->it_value.tv_sec < 0) {
                errno = EINVAL;
                return -1;
        }

        else if (ovalue)
                if (!git_getitimer(which, ovalue))
                        return -1; /* errno set in git_getitimer() */

        else
        switch (which) {
                case ITIMER_REAL:
                        alarm(value->it_value.tv_sec +
                                (value->it_value.tv_usec > 0) ? 1 : 0);
                        ret = 0; /* if alarm() fails we get a SIGLIMIT */
                        break;
                case ITIMER_VIRTUAL: /* FALLTHRU */
                case ITIMER_PROF: errno = ENOTSUP; ret = -1; break;
                default: errno = EINVAL; ret = -1;
        }

        return ret;
}


Worth being added to compat/, e.g. as setitimer.c, or, as itimer.c (as a by-product, it has getitimer() too)?

Bye, Jojo