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v0.5.1
https://github.com/python/cpython
09 December 2020, 11:06:31 UTC
Revision 05455637f3ba9bacd459700f4feab783e5967d69 authored by Miss Islington (bot) on 26 March 2018, 20:14:09 UTC, committed by GitHub on 26 March 2018, 20:14:09 UTC 
bpo-32844: Fix a subprocess misredirection of a low fd (GH5689)
 

bpo-32844: subprocess: Fix a potential misredirection of a low fd to stderr.

When redirecting, subprocess attempts to achieve the following state:
each fd to be redirected to is less than or equal to the fd
it is redirected from, which is necessary because redirection
occurs in the ascending order of destination descriptors.
It fails to do so in a couple of corner cases,
for example, if 1 is redirected to 2 and 0 is closed in the parent.
(cherry picked from commit 0e7144b064a19493a146af94175a087b3888c37b)

Co-authored-by: Alexey Izbyshev <izbyshev@users.noreply.github.com>
1 parent c6147ac
Raw File
Tip revision: 05455637f3ba9bacd459700f4feab783e5967d69 authored by Miss Islington (bot) on 26 March 2018, 20:14:09 UTC
bpo-32844: Fix a subprocess misredirection of a low fd (GH5689)
Tip revision: 0545563
printgrammar.c 

/* Print a bunch of C initializers that represent a grammar */

#define PGEN

#include "pgenheaders.h"
#include "grammar.h"

/* Forward */
static void printarcs(int, dfa *, FILE *);
static void printstates(grammar *, FILE *);
static void printdfas(grammar *, FILE *);
static void printlabels(grammar *, FILE *);

void
printgrammar(grammar *g, FILE *fp)
{
    fprintf(fp, "/* Generated by Parser/pgen */\n\n");
    fprintf(fp, "#include \"pgenheaders.h\"\n");
    fprintf(fp, "#include \"grammar.h\"\n");
    fprintf(fp, "PyAPI_DATA(grammar) _PyParser_Grammar;\n");
    printdfas(g, fp);
    printlabels(g, fp);
    fprintf(fp, "grammar _PyParser_Grammar = {\n");
    fprintf(fp, "    %d,\n", g->g_ndfas);
    fprintf(fp, "    dfas,\n");
    fprintf(fp, "    {%d, labels},\n", g->g_ll.ll_nlabels);
    fprintf(fp, "    %d\n", g->g_start);
    fprintf(fp, "};\n");
}

void
printnonterminals(grammar *g, FILE *fp)
{
    dfa *d;
    int i;

    fprintf(fp, "/* Generated by Parser/pgen */\n\n");

    d = g->g_dfa;
    for (i = g->g_ndfas; --i >= 0; d++)
        fprintf(fp, "#define %s %d\n", d->d_name, d->d_type);
}

static void
printarcs(int i, dfa *d, FILE *fp)
{
    arc *a;
    state *s;
    int j, k;

    s = d->d_state;
    for (j = 0; j < d->d_nstates; j++, s++) {
        fprintf(fp, "static arc arcs_%d_%d[%d] = {\n",
            i, j, s->s_narcs);
        a = s->s_arc;
        for (k = 0; k < s->s_narcs; k++, a++)
            fprintf(fp, "    {%d, %d},\n", a->a_lbl, a->a_arrow);
        fprintf(fp, "};\n");
    }
}

static void
printstates(grammar *g, FILE *fp)
{
    state *s;
    dfa *d;
    int i, j;

    d = g->g_dfa;
    for (i = 0; i < g->g_ndfas; i++, d++) {
        printarcs(i, d, fp);
        fprintf(fp, "static state states_%d[%d] = {\n",
            i, d->d_nstates);
        s = d->d_state;
        for (j = 0; j < d->d_nstates; j++, s++)
            fprintf(fp, "    {%d, arcs_%d_%d},\n",
                s->s_narcs, i, j);
        fprintf(fp, "};\n");
    }
}

static void
printdfas(grammar *g, FILE *fp)
{
    dfa *d;
    int i, j, n;

    printstates(g, fp);
    fprintf(fp, "static dfa dfas[%d] = {\n", g->g_ndfas);
    d = g->g_dfa;
    for (i = 0; i < g->g_ndfas; i++, d++) {
        fprintf(fp, "    {%d, \"%s\", %d, %d, states_%d,\n",
            d->d_type, d->d_name, d->d_initial, d->d_nstates, i);
        fprintf(fp, "     \"");
        n = NBYTES(g->g_ll.ll_nlabels);
        for (j = 0; j < n; j++)
            fprintf(fp, "\\%03o", d->d_first[j] & 0xff);
        fprintf(fp, "\"},\n");
    }
    fprintf(fp, "};\n");
}

static void
printlabels(grammar *g, FILE *fp)
{
    label *l;
    int i;

    fprintf(fp, "static label labels[%d] = {\n", g->g_ll.ll_nlabels);
    l = g->g_ll.ll_label;
    for (i = g->g_ll.ll_nlabels; --i >= 0; l++) {
        if (l->lb_str == NULL)
            fprintf(fp, "    {%d, 0},\n", l->lb_type);
        else
            fprintf(fp, "    {%d, \"%s\"},\n",
                l->lb_type, l->lb_str);
    }
    fprintf(fp, "};\n");
}
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