Example #1
0
jzfile *
ZIP_Put_In_Cache0(const char *name, ZFILE zfd, char **pmsg, jlong lastModified,
                 jboolean usemmap)
{
    static char errbuf[256];
    jlong len;
    jzfile *zip;

    if ((zip = allocZip(name)) == NULL) {
        return NULL;
    }

#ifdef USE_MMAP
    zip->usemmap = usemmap;
#endif
    zip->refs = 1;
    zip->lastModified = lastModified;

    if (zfd == -1) {
        if (pmsg && JVM_GetLastErrorString(errbuf, sizeof(errbuf)) > 0)
            *pmsg = errbuf;
        freeZip(zip);
        return NULL;
    }

    len = zip->len = IO_Lseek(zfd, 0, SEEK_END);	//获取当前jar/zip文件的长度
    if (len <= 0) {
        if (len == 0) { /* zip file is empty */
            if (pmsg) {
                *pmsg = "zip file is empty";
            }
        } else { /* error */
            if (pmsg && JVM_GetLastErrorString(errbuf, sizeof(errbuf)) > 0)
                *pmsg = errbuf;
        }
        ZFILE_Close(zfd);
        freeZip(zip);
        return NULL;
    }

    zip->zfd = zfd; //当前jar/zip文件的文件描述符

    if (readCEN(zip, -1) < 0) {
        /* An error occurred while trying to read the zip file */
        if (pmsg != 0) {
            /* Set the zip error message */
            *pmsg = zip->msg;
        }
        freeZip(zip);
        return NULL;
    }

    MLOCK(zfiles_lock);
    zip->next = zfiles;
    zfiles = zip;
    MUNLOCK(zfiles_lock);

    return zip;
}
Example #2
0
/*
 * Reads zip file central directory. Returns the file position of first
 * CEN header, otherwise returns -1 if an error occured. If zip->msg != NULL
 * then the error was a zip format error and zip->msg has the error text.
 * Always pass in -1 for knownTotal; it's used for a recursive call.
 */
static jlong
readCEN(jzfile *zip, jint knownTotal)
{
    /* Following are unsigned 32-bit */
    jlong endpos, end64pos, cenpos, cenlen, cenoff;
    /* Following are unsigned 16-bit */
    jint total, tablelen, i, j;
    unsigned char *cenbuf = NULL;
    unsigned char *cenend;
    unsigned char *cp;
#ifdef USE_MMAP
    static jlong pagesize;
    jlong offset;
#endif
    unsigned char endbuf[ENDHDR];
    jint endhdrlen = ENDHDR;
    jzcell *entries;
    jint *table;

    /* Clear previous zip error */
    zip->msg = NULL;
    /* Get position of END header */
    if ((endpos = findEND(zip, endbuf)) == -1)
        return -1; /* no END header or system error */

    if (endpos == 0) return 0;  /* only END header present */

    freeCEN(zip);
   /* Get position and length of central directory */
    cenlen = ENDSIZ(endbuf);
    cenoff = ENDOFF(endbuf);
    total  = ENDTOT(endbuf);
    if (cenlen == ZIP64_MAGICVAL || cenoff == ZIP64_MAGICVAL ||
        total == ZIP64_MAGICCOUNT) {
        unsigned char end64buf[ZIP64_ENDHDR];
        if ((end64pos = findEND64(zip, end64buf, endpos)) != -1) {
            cenlen = ZIP64_ENDSIZ(end64buf);
            cenoff = ZIP64_ENDOFF(end64buf);
            total = (jint)ZIP64_ENDTOT(end64buf);
            endpos = end64pos;
            endhdrlen = ZIP64_ENDHDR;
        }
    }

    if (cenlen > endpos)
        ZIP_FORMAT_ERROR("invalid END header (bad central directory size)");
    cenpos = endpos - cenlen;

    /* Get position of first local file (LOC) header, taking into
     * account that there may be a stub prefixed to the zip file. */
    zip->locpos = cenpos - cenoff;
    if (zip->locpos < 0)
        ZIP_FORMAT_ERROR("invalid END header (bad central directory offset)");

#ifdef USE_MMAP
    if (zip->usemmap) {
      /* On Solaris & Linux prior to JDK 6, we used to mmap the whole jar file to
       * read the jar file contents. However, this greatly increased the perceived
       * footprint numbers because the mmap'ed pages were adding into the totals shown
       * by 'ps' and 'top'. We switched to mmaping only the central directory of jar
       * file while calling 'read' to read the rest of jar file. Here are a list of
       * reasons apart from above of why we are doing so:
       * 1. Greatly reduces mmap overhead after startup complete;
       * 2. Avoids dual path code maintainance;
       * 3. Greatly reduces risk of address space (not virtual memory) exhaustion.
       */
        if (pagesize == 0) {
            pagesize = (jlong)sysconf(_SC_PAGESIZE);
            if (pagesize == 0) goto Catch;
        }
        if (cenpos > pagesize) {
            offset = cenpos & ~(pagesize - 1);
        } else {
            offset = 0;
        }
        /* When we are not calling recursively, knownTotal is -1. */
        if (knownTotal == -1) {
            void* mappedAddr;
            /* Mmap the CEN and END part only. We have to figure
               out the page size in order to make offset to be multiples of
               page size.
            */
            zip->mlen = cenpos - offset + cenlen + endhdrlen;
            zip->offset = offset;
            mappedAddr = mmap64(0, zip->mlen, PROT_READ, MAP_SHARED, zip->zfd, (off64_t) offset);
            zip->maddr = (mappedAddr == (void*) MAP_FAILED) ? NULL :
                (unsigned char*)mappedAddr;

            if (zip->maddr == NULL) {
                jio_fprintf(stderr, "mmap failed for CEN and END part of zip file\n");
                goto Catch;
            }
        }
        cenbuf = zip->maddr + cenpos - offset;
    } else
#endif
    {
        if ((cenbuf = malloc((size_t) cenlen)) == NULL ||
            (readFullyAt(zip->zfd, cenbuf, cenlen, cenpos) == -1))
        goto Catch;
    }

    cenend = cenbuf + cenlen;

    /* Initialize zip file data structures based on the total number
     * of central directory entries as stored in ENDTOT.  Since this
     * is a 2-byte field, but we (and other zip implementations)
     * support approx. 2**31 entries, we do not trust ENDTOT, but
     * treat it only as a strong hint.  When we call ourselves
     * recursively, knownTotal will have the "true" value.
     *
     * Keep this path alive even with the Zip64 END support added, just
     * for zip files that have more than 0xffff entries but don't have
     * the Zip64 enabled.
     */
    total = (knownTotal != -1) ? knownTotal : total;
    entries  = zip->entries  = calloc(total, sizeof(entries[0]));
    tablelen = zip->tablelen = ((total/2) | 1); // Odd -> fewer collisions
    table    = zip->table    = malloc(tablelen * sizeof(table[0]));
    if (entries == NULL || table == NULL) goto Catch;
    for (j = 0; j < tablelen; j++)
        table[j] = ZIP_ENDCHAIN;

    /* Iterate through the entries in the central directory */
    for (i = 0, cp = cenbuf; cp <= cenend - CENHDR; i++, cp += CENSIZE(cp)) {
        /* Following are unsigned 16-bit */
        jint method, nlen;
        unsigned int hsh;

        if (i >= total) {
            /* This will only happen if the zip file has an incorrect
             * ENDTOT field, which usually means it contains more than
             * 65535 entries. */
            cenpos = readCEN(zip, countCENHeaders(cenbuf, cenend));
            goto Finally;
        }

        method = CENHOW(cp);
        nlen   = CENNAM(cp);

        if (GETSIG(cp) != CENSIG)
            ZIP_FORMAT_ERROR("invalid CEN header (bad signature)");
        if (CENFLG(cp) & 1)
            ZIP_FORMAT_ERROR("invalid CEN header (encrypted entry)");
        if (method != STORED && method != DEFLATED)
            ZIP_FORMAT_ERROR("invalid CEN header (bad compression method)");
        if (cp + CENHDR + nlen > cenend)
            ZIP_FORMAT_ERROR("invalid CEN header (bad header size)");

        /* if the entry is metadata add it to our metadata names */
        if (isMetaName((char *)cp+CENHDR, nlen))
            if (addMetaName(zip, (char *)cp+CENHDR, nlen) != 0)
                goto Catch;

        /* Record the CEN offset and the name hash in our hash cell. */
        entries[i].cenpos = cenpos + (cp - cenbuf);
        entries[i].hash = hashN((char *)cp+CENHDR, nlen);

        /* Add the entry to the hash table */
        hsh = entries[i].hash % tablelen;
        entries[i].next = table[hsh];
        table[hsh] = i;
    }
    if (cp != cenend)
        ZIP_FORMAT_ERROR("invalid CEN header (bad header size)");

    zip->total = i;
    goto Finally;

 Catch:
    freeCEN(zip);
    cenpos = -1;

 Finally:
#ifdef USE_MMAP
    if (!zip->usemmap)
#endif
        free(cenbuf);

    return cenpos;
}
Example #3
0
jzfile *
ZIP_Put_In_Cache0(const char *name, ZFILE zfd, char **pmsg, jlong lastModified,
                 jboolean usemmap)
{
    char errbuf[256];
    jlong len;
    jzfile *zip;

    if ((zip = allocZip(name)) == NULL) {
        return NULL;
    }

#ifdef USE_MMAP
    zip->usemmap = usemmap;
#endif
    zip->refs = 1;
    zip->lastModified = lastModified;

    if (zfd == -1) {
        if (pmsg && getLastErrorString(errbuf, sizeof(errbuf)) > 0)
            *pmsg = strdup(errbuf);
        freeZip(zip);
        return NULL;
    }

    // Assumption, zfd refers to start of file. Trivially, reuse errbuf.
    if (readFully(zfd, errbuf, 4) != -1) {  // errors will be handled later
        zip->locsig = LOCSIG_AT(errbuf) ? JNI_TRUE : JNI_FALSE;
    }

    len = zip->len = IO_Lseek(zfd, 0, SEEK_END);
    if (len <= 0) {
        if (len == 0) { /* zip file is empty */
            if (pmsg) {
                *pmsg = strdup("zip file is empty");
            }
        } else { /* error */
            if (pmsg && getLastErrorString(errbuf, sizeof(errbuf)) > 0)
                *pmsg = strdup(errbuf);
        }
        ZFILE_Close(zfd);
        freeZip(zip);
        return NULL;
    }

    zip->zfd = zfd;
    if (readCEN(zip, -1) < 0) {
        /* An error occurred while trying to read the zip file */
        if (pmsg != 0) {
            /* Set the zip error message */
            if (zip->msg != NULL)
                *pmsg = strdup(zip->msg);
        }
        freeZip(zip);
        return NULL;
    }
    MLOCK(zfiles_lock);
    zip->next = zfiles;
    zfiles = zip;
    MUNLOCK(zfiles_lock);

    return zip;
}