Subversion Repositories planix.SVN

#include "lib.h"
#include <stdlib.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <dirent.h>
#include <unistd.h>
#include <string.h>
#include <signal.h>
#include "sys9.h"
#include "dir.h"

/*
 * Called before main to initialize environ.
 * Some plan9 environment variables
 * have 0 bytes in them (notably $path);
 * we change them to 1's (and execve changes back)
 *
 * Also, register the note handler.
 */

char **environ;
int errno;
unsigned long _clock;

static void fdsetup(char *, char *);
static void sigsetup(char *, char *);

enum {
        Envhunk=7000,
};

void
_envsetup(void)
{
        int dfd, fdinited, n, nd, m, i, j, f, nohandle, psize, cnt;
        char *ps, *p;
        char **pp;
        char name[NAME_MAX+5];
        Dir *d9, *d9a;
        static char **emptyenvp = 0;

        environ = emptyenvp;            /* pessimism */
        nohandle = 0;
        fdinited = 0;
        cnt = 0;
        strcpy(name, "#e");
        dfd = _OPEN(name, 0);
        if(dfd < 0)
                return;
        name[2] = '/';
        ps = p = malloc(Envhunk);
        if(p == 0)
                return;
        psize = Envhunk;
        nd = _dirreadall(dfd, &d9a);
        _CLOSE(dfd);
        for(j=0; j<nd; j++){
                d9 = &d9a[j];
                n = strlen(d9->name);
                if(n >= sizeof name - 4)
                        continue;       /* shouldn't be possible */
                m = d9->length;
                i = p - ps;
                if(i+n+1+m+1 > psize) {
                        psize += (n+m+2 < Envhunk)? Envhunk : n+m+2;
                        ps = realloc(ps, psize);
                        if (ps == 0) {
                                free(d9a);
                                return;
                        }
                        p = ps + i;
                }
                memcpy(p, d9->name, n);
                p[n] = '=';
                strcpy(name+3, d9->name);
                f = _OPEN(name, O_RDONLY);
                if(f < 0 || _READ(f, p+n+1, m) != m)
                        m = 0;
                _CLOSE(f);
                if(p[n+m] == 0)
                        m--;
                for(i=0; i<m; i++)
                        if(p[n+1+i] == 0)
                                p[n+1+i] = 1;
                p[n+1+m] = 0;
                if(strcmp(d9->name, "_fdinfo") == 0) {
                        _fdinit(p+n+1, p+n+1+m);
                        fdinited = 1;
                } else if(strcmp(d9->name, "_sighdlr") == 0)
                        sigsetup(p+n+1, p+n+1+m);
                else if(strcmp(d9->name, "nohandle") == 0)
                        nohandle = 1;
                p += n+m+2;
                cnt++;
        }
        free(d9a);
        if(!fdinited)
                _fdinit(0, 0);
        pp = malloc((1+cnt)*sizeof(char *));
        if (pp == 0)
                return;
        environ = pp;
        p = ps;
        for(i = 0; i < cnt; i++) {
                *pp++ = p;
                p = memchr(p, 0, ps+psize-p);
                if (!p)
                        break;
                p++;
        }
        *pp = 0;
        if(!nohandle)
                _NOTIFY(_notehandler);
}

static void
sigsetup(char *s, char *se)
{
        int sig;
        char *e;

        while(s < se){
                sig = strtoul(s, &e, 10);
                if(s == e)
                        break;
                s = e;
                if(sig <= MAXSIG)
                        _sighdlr[sig] = SIG_IGN;
        }
}