githubmirror/FFmpeg

tools/coverity.c
97 строк3 KB
Michael Niedermayer
tools/coverity: Phase 1 study of anti-halicogenic for coverity av_rescale()
08 июл 2024, 00:36
08 июл 2024, 00:36380a821
/* Coverity Scan model
*
* Copyright (C) 2014 Red Hat, Inc.
*
* Authors:
* Markus Armbruster <armbru@redhat.com>
* Paolo Bonzini <pbonzini@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or, at your
* option, any later version. See the COPYING file in the top-level directory.
*/
/*
* This is the source code for our Coverity user model file. The
* purpose of user models is to increase scanning accuracy by explaining
* code Coverity can't see (out of tree libraries) or doesn't
* sufficiently understand. Better accuracy means both fewer false
* positives and more true defects. Memory leaks in particular.
*
* - A model file can't import any header files. Some built-in primitives are
* available but not wchar_t, NULL etc.
* - Modeling doesn't need full structs and typedefs. Rudimentary structs
* and similar types are sufficient.
* - An uninitialized local variable signifies that the variable could be
* any value.
*
* The model file must be uploaded by an admin in the analysis settings of
* https://scan.coverity.com/projects/54
*
* above text is based on https://github.com/qemu/qemu/blob/master/scripts/coverity-model.c
*/

#define NULL (void *)0

typedef long long int64_t;

enum AVRounding {
    AV_ROUND_ZERO     = 0,
    AV_ROUND_INF      = 1,
    AV_ROUND_DOWN     = 2,
    AV_ROUND_UP       = 3,
    AV_ROUND_NEAR_INF = 5,
    AV_ROUND_PASS_MINMAX = 8192,
};

// Based on https://scan.coverity.com/models
void *av_malloc(size_t size) {
    int has_memory;
    __coverity_negative_sink__(size);
    if (has_memory) {
        void *ptr = __coverity_alloc__(size);
        __coverity_mark_as_uninitialized_buffer__(ptr);
        __coverity_mark_as_afm_allocated__(ptr, "av_free");
         return ptr;
    } else {
        return 0;
    }
}

void *av_mallocz(size_t size) {
    int has_memory;
    __coverity_negative_sink__(size);
    if (has_memory) {
        void *ptr = __coverity_alloc__(size);
        __coverity_writeall0__(ptr);
        __coverity_mark_as_afm_allocated__(ptr, "av_free");
        return ptr;
    } else {
        return 0;
    }
}

void *av_realloc(void *ptr, size_t size) {
    int has_memory;
    __coverity_negative_sink__(size);
    if (has_memory) {
        __coverity_escape__(ptr);
        ptr = __coverity_alloc__(size);
        __coverity_writeall__(ptr);
        __coverity_mark_as_afm_allocated__(ptr, "av_free");
        return ptr;
    } else {
        return 0;
    }
}

void *av_free(void *ptr) {
    __coverity_free__(ptr);
    __coverity_mark_as_afm_freed__(ptr, "av_free");
}


int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding rnd) {
    __coverity_negative_sink__(b);
    __coverity_negative_sink__(c);

    return (double)a * (double)b / (double)c;
}