p_cache.c

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// SPDX-FileCopyrightText: 2017-2018 condret <condr3t@protonmail.com>
// SPDX-FileCopyrightText: 2017-2018 alvaro <alvaro.felipe91@gmail.com>
// SPDX-License-Identifier: LGPL-3.0-only
 
#include <rz_io.h>
#include <rz_types.h>
#include <string.h>
 
const ut64 cleanup_masks[] = {
    0x0000000000000001,
    0x0000000000000003,
    0x0000000000000007,
    0x000000000000000f,
    0x000000000000001f,
    0x000000000000003f,
    0x000000000000007f,
    0x00000000000000ff,
    0x00000000000001ff,
    0x00000000000003ff,
    0x00000000000007ff,
    0x0000000000000fff,
    0x0000000000001fff,
    0x0000000000003fff,
    0x0000000000007fff,
    0x000000000000ffff,
    0x000000000001ffff,
    0x000000000003ffff,
    0x000000000007ffff,
    0x00000000000fffff,
    0x00000000001fffff,
    0x00000000003fffff,
    0x00000000007fffff,
    0x0000000000ffffff,
    0x0000000001ffffff,
    0x0000000003ffffff,
    0x0000000007ffffff,
    0x000000000fffffff,
    0x000000001fffffff,
    0x000000003fffffff,
    0x000000007fffffff,
    0x00000000ffffffff,
    0x00000001ffffffff,
    0x00000003ffffffff,
    0x00000007ffffffff,
    0x0000000fffffffff,
    0x0000001fffffffff,
    0x0000003fffffffff,
    0x0000007fffffffff,
    0x000000ffffffffff,
    0x000001ffffffffff,
    0x000003ffffffffff,
    0x000007ffffffffff,
    0x00000fffffffffff,
    0x00001fffffffffff,
    0x00003fffffffffff,
    0x00007fffffffffff,
    0x0000ffffffffffff,
    0x0001ffffffffffff,
    0x0003ffffffffffff,
    0x0007ffffffffffff,
    0x000fffffffffffff,
    0x001fffffffffffff,
    0x003fffffffffffff,
    0x007fffffffffffff,
    0x00ffffffffffffff,
    0x01ffffffffffffff,
    0x03ffffffffffffff,
    0x07ffffffffffffff,
    0x0fffffffffffffff,
    0x1fffffffffffffff,
    0x3fffffffffffffff,
    0x7fffffffffffffff
};
 
static void pcache_kv_free(HtUPKv *kv) {
    free(kv->value);
}
 
RZ_API bool rz_io_desc_cache_init(RzIODesc *desc) {
    if (!desc || desc->cache) {
        return false;
    }
    return (desc->cache = ht_up_new(NULL, pcache_kv_free, NULL)) ? true : false;
}
 
RZ_API int rz_io_desc_cache_write(RzIODesc *desc, ut64 paddr, const ut8 *buf, int len) {
    RzIODescCache *cache;
    ut64 caddr, desc_sz = rz_io_desc_size(desc);
    int cbaddr, written = 0;
    if ((len < 1) || !desc || (desc_sz <= paddr) ||
        !desc->io || (!desc->cache && !rz_io_desc_cache_init(desc))) {
        return 0;
    }
    if (len > desc_sz) {
        len = (int)desc_sz;
    }
    if (paddr > (desc_sz - len)) {
        len = (int)(desc_sz - paddr);
    }
    caddr = paddr / RZ_IO_DESC_CACHE_SIZE;
    cbaddr = paddr % RZ_IO_DESC_CACHE_SIZE;
    while (written < len) {
        // get an existing desc-cache, if it exists
        if (!(cache = (RzIODescCache *)ht_up_find(desc->cache, caddr, NULL))) {
            // create new desc-cache
            cache = RZ_NEW0(RzIODescCache);
            if (!cache) {
                return 0;
            }
            // feed ht with the new desc-cache
            ht_up_insert(desc->cache, caddr, cache);
        }
        // check if the remaining data fits into the cache
        if ((len - written) > (RZ_IO_DESC_CACHE_SIZE - cbaddr)) {
            written += (RZ_IO_DESC_CACHE_SIZE - cbaddr);
            // this can be optimized
            for (; cbaddr < RZ_IO_DESC_CACHE_SIZE; cbaddr++) {
                // write to cache
                cache->cdata[cbaddr] = *buf;
                // save, that its cached
                cache->cached |= (0x1ULL << cbaddr);
                buf++;
            }
        } else {
            // XXX this looks like very suspicious
            do {
                cache->cdata[cbaddr] = *buf;
                cache->cached |= (0x1ULL << cbaddr);
                buf++;
                written++;
                cbaddr++;
            } while (len > written);
        }
        caddr++;
        cbaddr = 0;
    }
    RzEventIOWrite iow = { paddr, buf, len };
    rz_event_send(desc->io->event, RZ_EVENT_IO_WRITE, &iow);
    return written;
}
 
RZ_API int rz_io_desc_cache_read(RzIODesc *desc, ut64 paddr, ut8 *buf, int len) {
    RzIODescCache *cache;
    ut8 *ptr = buf;
    ut64 caddr, desc_sz = rz_io_desc_size(desc);
    int cbaddr, amount = 0;
    if ((len < 1) || !desc || (desc_sz <= paddr) || !desc->io || !desc->cache) {
        return 0;
    }
    if (len > desc_sz) {
        len = (int)desc_sz;
    }
    if (paddr > (desc_sz - len)) {
        len = (int)(desc_sz - paddr);
    }
    caddr = paddr / RZ_IO_DESC_CACHE_SIZE;
    cbaddr = paddr % RZ_IO_DESC_CACHE_SIZE;
    while (amount < len) {
        // get an existing desc-cache, if it exists
        if (!(cache = (RzIODescCache *)ht_up_find(desc->cache, caddr, NULL))) {
            amount += (RZ_IO_DESC_CACHE_SIZE - cbaddr);
            ptr += (RZ_IO_DESC_CACHE_SIZE - cbaddr);
            goto beach;
        }
        if ((len - amount) > (RZ_IO_DESC_CACHE_SIZE - cbaddr)) {
            amount += (RZ_IO_DESC_CACHE_SIZE - cbaddr);
            for (; cbaddr < RZ_IO_DESC_CACHE_SIZE; cbaddr++) {
                if (cache->cached & (0x1ULL << cbaddr)) {
                    *ptr = cache->cdata[cbaddr];
                }
                ptr++;
            }
        } else {
            do {
                if (cache->cached & (0x1ULL << cbaddr)) {
                    *ptr = cache->cdata[cbaddr];
                }
                ptr++;
                amount++;
                cbaddr++;
            } while (len > amount);
        }
    beach:
        caddr++;
        cbaddr = 0;
    }
    return amount;
}
 
static void __riocache_free(void *user) {
    RzIOCache *cache = (RzIOCache *)user;
    if (cache) {
        free(cache->data);
        free(cache->odata);
    }
    free(cache);
}
 
static bool __desc_cache_list_cb(void *user, const ut64 k, const void *v) {
    RzList *writes = (RzList *)user;
    RzIOCache *cache = NULL;
    ut64 blockaddr;
    int byteaddr, i;
    if (!writes) {
        return false;
    }
    const RzIODescCache *dcache = v;
    blockaddr = k * RZ_IO_DESC_CACHE_SIZE;
    for (i = byteaddr = 0; byteaddr < RZ_IO_DESC_CACHE_SIZE; byteaddr++) {
        if (dcache->cached & (0x1LL << byteaddr)) {
            if (!cache) {
                cache = RZ_NEW0(RzIOCache);
                if (!cache) {
                    return false;
                }
                cache->data = malloc(RZ_IO_DESC_CACHE_SIZE - byteaddr);
                if (!cache->data) {
                    free(cache);
                    return false;
                }
                cache->itv.addr = blockaddr + byteaddr;
            }
            cache->data[i] = dcache->cdata[byteaddr];
            i++;
        } else if (cache) {
            ut8 *data = realloc(cache->data, i);
            if (!data) {
                __riocache_free((void *)cache);
                return false;
            }
            cache->data = data;
            cache->itv.size = i;
            i = 0;
            rz_list_push(writes, cache);
            cache = NULL;
        }
    }
    if (cache) {
#if 0
        cache->size = i;
        cache->to = blockaddr + RZ_IO_DESC_CACHE_SIZE;
#endif
        cache->itv.size = i;
        rz_list_push(writes, cache);
    }
    return true;
}
 
RZ_API RzList *rz_io_desc_cache_list(RzIODesc *desc) {
    if (!desc || !desc->io || !desc->io->desc || !desc->io->p_cache || !desc->cache) {
        return NULL;
    }
    RzList *writes = rz_list_newf((RzListFree)__riocache_free);
    if (!writes) {
        return NULL;
    }
    ht_up_foreach(desc->cache, __desc_cache_list_cb, writes);
    RzIODesc *current = desc->io->desc;
    desc->io->desc = desc;
    desc->io->p_cache = false;
 
    RzIOCache *c;
    RzListIter *iter;
    rz_list_foreach (writes, iter, c) {
        const ut64 itvSize = rz_itv_size(c->itv);
        c->odata = calloc(1, itvSize);
        if (!c->odata) {
            rz_list_free(writes);
            return NULL;
        }
        rz_io_pread_at(desc->io, rz_itv_begin(c->itv), c->odata, itvSize);
    }
    desc->io->p_cache = true;
    desc->io->desc = current;
    return writes;
}
 
static bool __desc_cache_commit_cb(void *user, const ut64 k, const void *v) {
    RzIODesc *desc = (RzIODesc *)user;
    int byteaddr, i;
    ut8 buf[RZ_IO_DESC_CACHE_SIZE] = { 0 };
    if (!desc || !desc->io) {
        return false;
    }
    const RzIODescCache *dcache = v;
    ut64 blockaddr = RZ_IO_DESC_CACHE_SIZE * k;
    for (i = byteaddr = 0; byteaddr < RZ_IO_DESC_CACHE_SIZE; byteaddr++) {
        if (dcache->cached & (0x1LL << byteaddr)) {
            buf[i] = dcache->cdata[byteaddr];
            i++;
        } else if (i > 0) {
            rz_io_pwrite_at(desc->io, blockaddr + byteaddr - i, buf, i);
            i = 0;
        }
    }
    if (i > 0) {
        rz_io_pwrite_at(desc->io, blockaddr + RZ_IO_DESC_CACHE_SIZE - i, buf, i);
    }
    return true;
}
 
RZ_API bool rz_io_desc_cache_commit(RzIODesc *desc) {
    RzIODesc *current;
    if (!desc || !(desc->perm & RZ_PERM_W) || !desc->io || !desc->io->files || !desc->io->p_cache) {
        return false;
    }
    if (!desc->cache) {
        return true;
    }
    current = desc->io->desc;
    desc->io->desc = desc;
    desc->io->p_cache = false;
    ht_up_foreach(desc->cache, __desc_cache_commit_cb, desc);
    ht_up_free(desc->cache);
    desc->cache = NULL;
    desc->io->p_cache = true;
    desc->io->desc = current;
    return true;
}
 
static bool __desc_cache_cleanup_cb(void *user, const ut64 k, const void *v) {
    RzIODesc *desc = (RzIODesc *)user;
    ut64 size, blockaddr;
    int byteaddr;
    if (!desc || !desc->cache) {
        return false;
    }
    RzIODescCache *cache = (RzIODescCache *)v;
    blockaddr = RZ_IO_DESC_CACHE_SIZE * k;
    size = rz_io_desc_size(desc);
    if (size <= blockaddr) {
        ht_up_delete(desc->cache, k);
        return true;
    }
    if (size <= (blockaddr + RZ_IO_DESC_CACHE_SIZE - 1)) {
        // this looks scary, but it isn't
        byteaddr = (int)(size - blockaddr) - 1;
        cache->cached &= cleanup_masks[byteaddr];
    }
    return true;
}
 
RZ_API void rz_io_desc_cache_cleanup(RzIODesc *desc) {
    if (desc && desc->cache) {
        ht_up_foreach(desc->cache, __desc_cache_cleanup_cb, desc);
    }
}
 
static bool __desc_fini_cb(void *user, void *data, ut32 id) {
    RzIODesc *desc = (RzIODesc *)data;
    if (desc->cache) {
        ht_up_free(desc->cache);
        desc->cache = NULL;
    }
    return true;
}
 
RZ_API void rz_io_desc_cache_fini(RzIODesc *desc) {
    __desc_fini_cb(NULL, (void *)desc, 0);
}
 
RZ_API void rz_io_desc_cache_fini_all(RzIO *io) {
    if (io && io->files) {
        rz_id_storage_foreach(io->files, __desc_fini_cb, NULL);
    }
}