source: branches/help/CORE/arb_strbuf.cxx

// ============================================================= //
//                                                               //
//   File      : arb_strbuf.cxx                                  //
//   Purpose   : "unlimited" output buffer                       //
//                                                               //
//   Institute of Microbiology (Technical University Munich)     //
//   http://www.arb-home.de/                                     //
//                                                               //
// ============================================================= //

#include "arb_strbuf.h"

void GBS_strstruct::vnprintf(size_t maxlen, const char *templat, va_list& parg) {
    ensure_mem(maxlen+1);

    char *buffer = data+pos;
    int   printed;

#ifdef LINUX
    printed = vsnprintf(buffer, maxlen+1, templat, parg);
#else
    printed = vsprintf(buffer, templat, parg);
#endif

    assert_or_exit(printed >= 0 && (size_t)printed <= maxlen);
    inc_pos(printed);
}

void GBS_strstruct::nprintf(size_t maxlen, const char *templat, ...) {
    va_list parg;
    va_start(parg, templat);
    vnprintf(maxlen, templat, parg);
}

// old interface

static GBS_strstruct last_used;

GBS_strstruct *GBS_stropen(long init_size) {
    /*! create a new memory file
     * @param init_size  estimated used size
     */

    GBS_strstruct *strstr = new GBS_strstruct;

    arb_assert(init_size>0);

    if (last_used.get_buffer_size() >= (size_t)init_size) {
        strstr->reassign_mem(last_used);

        static short oversized_counter = 0;

        if ((size_t)init_size*10 < strstr->get_buffer_size()) oversized_counter++;
        else oversized_counter = 0;

        if (oversized_counter>10) {                 // was oversized more than 10 times -> allocate smaller block
            size_t dummy;
            free(strstr->release_mem(dummy));
            strstr->alloc_mem(init_size);
        }
    }
    else {
        strstr->alloc_mem(init_size);
    }

    return strstr;
}

char *GBS_strclose(GBS_strstruct *strstr) {
    // returns a char* copy of the memory file
    char *str = strstr->get_copy();
    GBS_strforget(strstr);
    return str;
}

void GBS_strforget(GBS_strstruct *strstr) {
    size_t last_bsize = last_used.get_buffer_size();
    size_t curr_bsize = strstr->get_buffer_size();

    if (last_bsize < curr_bsize) { // last_used is smaller -> keep this
        last_used.reassign_mem(*strstr);
    }
    delete strstr;
}

char *GBS_mempntr(GBS_strstruct *strstr) {
    // returns the memory file (with write access)
    return (char*)strstr->get_data();
}

long GBS_memoffset(GBS_strstruct *strstr) {
    // returns the offset into the memory file
    return strstr->get_position();
}

void GBS_str_cut_tail(GBS_strstruct *strstr, size_t byte_count) {
    // Removes byte_count characters at the tail of a memfile
    strstr->cut_tail(byte_count);
}

void GBS_strncat(GBS_strstruct *strstr, const char *ptr, size_t len) {
    /* append some bytes string to strstruct
     * (caution : copies zero byte and mem behind if used with wrong len!)
     */
    strstr->ncat(ptr, len);
}

void GBS_strcat(GBS_strstruct *strstr, const char *ptr) {
    // append string to strstruct
    strstr->cat(ptr);
}

void GBS_strnprintf(GBS_strstruct *strstr, long maxlen, const char *templat, ...) {
    va_list parg;
    va_start(parg, templat);
    strstr->vnprintf(maxlen+2, templat, parg);
}

void GBS_chrcat(GBS_strstruct *strstr, char ch) {
    strstr->put(ch);
}

void GBS_chrncat(GBS_strstruct *strstr, char ch, size_t n) {
    strstr->nput(ch, n);
}

void GBS_intcat(GBS_strstruct *strstr, long val) {
    char buffer[100];
    long len = sprintf(buffer, "%li", val);
    GBS_strncat(strstr, buffer, len);
}

void GBS_floatcat(GBS_strstruct *strstr, double val) {
    char buffer[100];
    long len = sprintf(buffer, "%f", val);
    GBS_strncat(strstr, buffer, len);
}

// --------------------------------------------------------------------------------

#ifdef UNIT_TESTS
#ifndef TEST_UNIT_H
#include <test_unit.h>
#endif

void TEST_GBS_strstruct() {
    { GBS_strstruct buf; buf.put ('c');    TEST_EXPECT_EQUAL(buf.get_data(), "c");   }
    { GBS_strstruct buf; buf.cat ("abc");  TEST_EXPECT_EQUAL(buf.get_data(), "abc"); }
    { GBS_strstruct buf; buf.nput('x', 0); TEST_EXPECT_EQUAL(buf.get_data(), "");    }

    { GBS_strstruct buf; buf.ncat("abc", 0); TEST_EXPECT_EQUAL(buf.get_data(), ""); }
    { GBS_strstruct buf; buf.cat ("");       TEST_EXPECT_EQUAL(buf.get_data(), "");  }

    { GBS_strstruct buf; TEST_EXPECT_EQUAL(buf.get_data(), ""); }
}

#define EXPECT_CONTENT(content) TEST_EXPECT_EQUAL(GBS_mempntr(strstr), content)

void TEST_GBS_strstruct_old_interface() {
    // test the old, out-dated interface to GBS_strstruct (comes from pre-OO-times).

    {
        GBS_strstruct *strstr = GBS_stropen(1000); EXPECT_CONTENT("");

        GBS_chrncat(strstr, 'b', 3);        EXPECT_CONTENT("bbb");
        GBS_intcat(strstr, 17);             EXPECT_CONTENT("bbb17");
        GBS_chrcat(strstr, '_');            EXPECT_CONTENT("bbb17_");
        GBS_floatcat(strstr, 3.5);          EXPECT_CONTENT("bbb17_3.500000");

        TEST_EXPECT_EQUAL(GBS_memoffset(strstr), 14);
        GBS_str_cut_tail(strstr, 13);       EXPECT_CONTENT("b");
        GBS_strcat(strstr, "utter");        EXPECT_CONTENT("butter");
        GBS_strncat(strstr, "flying", 3);   EXPECT_CONTENT("butterfly");

        GBS_strnprintf(strstr, 200, "%c%s", ' ', "flutters");
        EXPECT_CONTENT("butterfly flutters");

        GBS_strforget(strstr);
    }
    {
        // re-alloc smaller
        GBS_strstruct *strstr = GBS_stropen(500); EXPECT_CONTENT("");
        GBS_strforget(strstr);
    }

    // trigger downsize of oversized block
    for (int i = 0; i<12; ++i) {
        GBS_strstruct *strstr = GBS_stropen(10);
        GBS_strforget(strstr);
    }

    {
        GBS_strstruct *strstr     = GBS_stropen(10);
        size_t         oldbufsize = strstr->get_buffer_size();
        GBS_chrncat(strstr, 'x', 20);               // trigger reallocation of buffer

        TEST_EXPECT_DIFFERENT(oldbufsize, strstr->get_buffer_size()); // did we reallocate?
        EXPECT_CONTENT("xxxxxxxxxxxxxxxxxxxx");
        GBS_strforget(strstr);
    }
}

#endif // UNIT_TESTS

// --------------------------------------------------------------------------------