Mon Mar 31 07:38:05 2008

Asterisk developer's documentation


translate.c

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00001 /*
00002  * Asterisk -- An open source telephony toolkit.
00003  *
00004  * Copyright (C) 1999 - 2006, Digium, Inc.
00005  *
00006  * Mark Spencer <markster@digium.com>
00007  *
00008  * See http://www.asterisk.org for more information about
00009  * the Asterisk project. Please do not directly contact
00010  * any of the maintainers of this project for assistance;
00011  * the project provides a web site, mailing lists and IRC
00012  * channels for your use.
00013  *
00014  * This program is free software, distributed under the terms of
00015  * the GNU General Public License Version 2. See the LICENSE file
00016  * at the top of the source tree.
00017  */
00018 
00019 /*! \file
00020  *
00021  * \brief Translate via the use of pseudo channels
00022  *
00023  * \author Mark Spencer <markster@digium.com> 
00024  */
00025 
00026 #include "asterisk.h"
00027 
00028 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
00029 
00030 #include <sys/types.h>
00031 #include <sys/socket.h>
00032 #include <sys/time.h>
00033 #include <unistd.h>
00034 #include <stdlib.h>
00035 #include <string.h>
00036 #include <stdio.h>
00037 
00038 #include "asterisk/lock.h"
00039 #include "asterisk/channel.h"
00040 #include "asterisk/logger.h"
00041 #include "asterisk/translate.h"
00042 #include "asterisk/module.h"
00043 #include "asterisk/options.h"
00044 #include "asterisk/frame.h"
00045 #include "asterisk/sched.h"
00046 #include "asterisk/cli.h"
00047 #include "asterisk/term.h"
00048 
00049 #define MAX_RECALC 200 /* max sample recalc */
00050 
00051 /*! \brief the list of translators */
00052 static AST_LIST_HEAD_STATIC(translators, ast_translator);
00053 
00054 struct translator_path {
00055    struct ast_translator *step;  /*!< Next step translator */
00056    unsigned int cost;      /*!< Complete cost to destination */
00057    unsigned int multistep;    /*!< Multiple conversions required for this translation */
00058 };
00059 
00060 /*! \brief a matrix that, for any pair of supported formats,
00061  * indicates the total cost of translation and the first step.
00062  * The full path can be reconstricted iterating on the matrix
00063  * until step->dstfmt == desired_format.
00064  *
00065  * Array indexes are 'src' and 'dest', in that order.
00066  *
00067  * Note: the lock in the 'translators' list is also used to protect
00068  * this structure.
00069  */
00070 static struct translator_path tr_matrix[MAX_FORMAT][MAX_FORMAT];
00071 
00072 /*! \todo
00073  * TODO: sample frames for each supported input format.
00074  * We build this on the fly, by taking an SLIN frame and using
00075  * the existing converter to play with it.
00076  */
00077 
00078 /*! \brief returns the index of the lowest bit set */
00079 static force_inline int powerof(unsigned int d)
00080 {
00081    int x = ffs(d);
00082 
00083    if (x)
00084       return x - 1;
00085 
00086    ast_log(LOG_WARNING, "No bits set? %d\n", d);
00087 
00088    return -1;
00089 }
00090 
00091 /*
00092  * wrappers around the translator routines.
00093  */
00094 
00095 /*!
00096  * \brief Allocate the descriptor, required outbuf space,
00097  * and possibly also plc and desc.
00098  */
00099 static void *newpvt(struct ast_translator *t)
00100 {
00101    struct ast_trans_pvt *pvt;
00102    int len;
00103    int useplc = t->plc_samples > 0 && t->useplc;   /* cache, because it can change on the fly */
00104    char *ofs;
00105 
00106    /*
00107     * compute the required size adding private descriptor,
00108     * plc, buffer, AST_FRIENDLY_OFFSET.
00109     */
00110    len = sizeof(*pvt) + t->desc_size;
00111    if (useplc)
00112       len += sizeof(plc_state_t);
00113    if (t->buf_size)
00114       len += AST_FRIENDLY_OFFSET + t->buf_size;
00115    pvt = ast_calloc(1, len);
00116    if (!pvt)
00117       return NULL;
00118    pvt->t = t;
00119    ofs = (char *)(pvt + 1);   /* pointer to data space */
00120    if (t->desc_size) {     /* first comes the descriptor */
00121       pvt->pvt = ofs;
00122       ofs += t->desc_size;
00123    }
00124    if (useplc) {        /* then plc state */
00125       pvt->plc = (plc_state_t *)ofs;
00126       ofs += sizeof(plc_state_t);
00127    }
00128    if (t->buf_size)     /* finally buffer and header */
00129       pvt->outbuf = ofs + AST_FRIENDLY_OFFSET;
00130    /* call local init routine, if present */
00131    if (t->newpvt && t->newpvt(pvt)) {
00132       free(pvt);
00133       return NULL;
00134    }
00135    ast_module_ref(t->module);
00136    return pvt;
00137 }
00138 
00139 static void destroy(struct ast_trans_pvt *pvt)
00140 {
00141    struct ast_translator *t = pvt->t;
00142 
00143    if (ast_test_flag(&pvt->f, AST_FRFLAG_FROM_TRANSLATOR)) {
00144       /* If this flag is still set, that means that the translation path has
00145        * been torn down, while we still have a frame out there being used.
00146        * When ast_frfree() gets called on that frame, this ast_trans_pvt
00147        * will get destroyed, too. */
00148 
00149       /* Set the magic hint that this has been requested to be destroyed. */
00150       pvt->datalen = -1;
00151 
00152       return;
00153    }
00154 
00155    if (t->destroy)
00156       t->destroy(pvt);
00157    free(pvt);
00158    ast_module_unref(t->module);
00159 }
00160 
00161 /*! \brief framein wrapper, deals with plc and bound checks.  */
00162 static int framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
00163 {
00164    int16_t *dst = (int16_t *)pvt->outbuf;
00165    int ret;
00166    int samples = pvt->samples;   /* initial value */
00167    
00168    /* Copy the last in jb timing info to the pvt */
00169    ast_copy_flags(&pvt->f, f, AST_FRFLAG_HAS_TIMING_INFO);
00170    pvt->f.ts = f->ts;
00171    pvt->f.len = f->len;
00172    pvt->f.seqno = f->seqno;
00173 
00174    if (f->samples == 0) {
00175       ast_log(LOG_WARNING, "no samples for %s\n", pvt->t->name);
00176    }
00177    if (pvt->t->buffer_samples) { /* do not pass empty frames to callback */
00178       if (f->datalen == 0) { /* perform PLC with nominal framesize of 20ms/160 samples */
00179          if (pvt->plc) {
00180             int l = pvt->t->plc_samples;
00181             if (pvt->samples + l > pvt->t->buffer_samples) {
00182                ast_log(LOG_WARNING, "Out of buffer space\n");
00183                return -1;
00184             }
00185             l = plc_fillin(pvt->plc, dst + pvt->samples, l);
00186             pvt->samples += l;
00187             pvt->datalen = pvt->samples * 2; /* SLIN has 2bytes for 1sample */
00188          }
00189          /* We don't want generic PLC. If the codec has native PLC, then do that */
00190          if (!pvt->t->native_plc)
00191             return 0;
00192       }
00193       if (pvt->samples + f->samples > pvt->t->buffer_samples) {
00194          ast_log(LOG_WARNING, "Out of buffer space\n");
00195          return -1;
00196       }
00197    }
00198    if ( f->data == NULL && f->datalen > 0 ) {
00199       ast_log(LOG_ERROR, "NULL pointer in frame data for %s\n", pvt->t->name);
00200       return -1;
00201    }
00202    /* we require a framein routine, wouldn't know how to do
00203     * it otherwise.
00204     */
00205    ret = pvt->t->framein(pvt, f);
00206    /* possibly store data for plc */
00207    if (!ret && pvt->plc) {
00208       int l = pvt->t->plc_samples;
00209       if (pvt->samples < l)
00210          l = pvt->samples;
00211       plc_rx(pvt->plc, dst + pvt->samples - l, l);
00212    }
00213    /* diagnostic ... */
00214    if (pvt->samples == samples)
00215       ast_log(LOG_WARNING, "%s did not update samples %d\n",
00216          pvt->t->name, pvt->samples);
00217         return ret;
00218 }
00219 
00220 /*! \brief generic frameout routine.
00221  * If samples and datalen are 0, take whatever is in pvt
00222  * and reset them, otherwise take the values in the caller and
00223  * leave alone the pvt values.
00224  */
00225 struct ast_frame *ast_trans_frameout(struct ast_trans_pvt *pvt,
00226    int datalen, int samples)
00227 {
00228    struct ast_frame *f = &pvt->f;
00229 
00230         if (samples)
00231       f->samples = samples;
00232    else {
00233       if (pvt->samples == 0)
00234          return NULL;
00235       f->samples = pvt->samples;
00236       pvt->samples = 0;
00237    }
00238    if (datalen)
00239       f->datalen = datalen;
00240    else {
00241       f->datalen = pvt->datalen;
00242       pvt->datalen = 0;
00243    }
00244 
00245    f->frametype = AST_FRAME_VOICE;
00246    f->subclass = 1 << (pvt->t->dstfmt);
00247    f->mallocd = 0;
00248    f->offset = AST_FRIENDLY_OFFSET;
00249    f->src = pvt->t->name;
00250    f->data = pvt->outbuf;
00251 
00252    ast_set_flag(f, AST_FRFLAG_FROM_TRANSLATOR);
00253 
00254    return f;
00255 }
00256 
00257 static struct ast_frame *default_frameout(struct ast_trans_pvt *pvt)
00258 {
00259    return ast_trans_frameout(pvt, 0, 0);
00260 }
00261 
00262 /* end of callback wrappers and helpers */
00263 
00264 void ast_translator_free_path(struct ast_trans_pvt *p)
00265 {
00266    struct ast_trans_pvt *pn = p;
00267    while ( (p = pn) ) {
00268       pn = p->next;
00269       destroy(p);
00270    }
00271 }
00272 
00273 /*! \brief Build a chain of translators based upon the given source and dest formats */
00274 struct ast_trans_pvt *ast_translator_build_path(int dest, int source)
00275 {
00276    struct ast_trans_pvt *head = NULL, *tail = NULL;
00277    
00278    source = powerof(source);
00279    dest = powerof(dest);
00280    
00281    AST_LIST_LOCK(&translators);
00282 
00283    while (source != dest) {
00284       struct ast_trans_pvt *cur;
00285       struct ast_translator *t = tr_matrix[source][dest].step;
00286       if (!t) {
00287          ast_log(LOG_WARNING, "No translator path from %s to %s\n", 
00288             ast_getformatname(source), ast_getformatname(dest));
00289          AST_LIST_UNLOCK(&translators);
00290          return NULL;
00291       }
00292       if (!(cur = newpvt(t))) {
00293          ast_log(LOG_WARNING, "Failed to build translator step from %d to %d\n", source, dest);
00294          if (head)
00295             ast_translator_free_path(head);  
00296          AST_LIST_UNLOCK(&translators);
00297          return NULL;
00298       }
00299       if (!head)
00300          head = cur;
00301       else
00302          tail->next = cur;
00303       tail = cur;
00304       cur->nextin = cur->nextout = ast_tv(0, 0);
00305       /* Keep going if this isn't the final destination */
00306       source = cur->t->dstfmt;
00307    }
00308 
00309    AST_LIST_UNLOCK(&translators);
00310    return head;
00311 }
00312 
00313 /*! \brief do the actual translation */
00314 struct ast_frame *ast_translate(struct ast_trans_pvt *path, struct ast_frame *f, int consume)
00315 {
00316    struct ast_trans_pvt *p = path;
00317    struct ast_frame *out = f;
00318    struct timeval delivery;
00319    int has_timing_info;
00320    long ts;
00321    long len;
00322    int seqno;
00323 
00324    has_timing_info = ast_test_flag(f, AST_FRFLAG_HAS_TIMING_INFO);
00325    ts = f->ts;
00326    len = f->len;
00327    seqno = f->seqno;
00328 
00329    /* XXX hmmm... check this below */
00330    if (!ast_tvzero(f->delivery)) {
00331       if (!ast_tvzero(path->nextin)) {
00332          /* Make sure this is in line with what we were expecting */
00333          if (!ast_tveq(path->nextin, f->delivery)) {
00334             /* The time has changed between what we expected and this
00335                most recent time on the new packet.  If we have a
00336                valid prediction adjust our output time appropriately */
00337             if (!ast_tvzero(path->nextout)) {
00338                path->nextout = ast_tvadd(path->nextout,
00339                           ast_tvsub(f->delivery, path->nextin));
00340             }
00341             path->nextin = f->delivery;
00342          }
00343       } else {
00344          /* This is our first pass.  Make sure the timing looks good */
00345          path->nextin = f->delivery;
00346          path->nextout = f->delivery;
00347       }
00348       /* Predict next incoming sample */
00349       path->nextin = ast_tvadd(path->nextin, ast_samp2tv(f->samples, ast_format_rate(f->subclass)));
00350    }
00351    delivery = f->delivery;
00352    for ( ; out && p ; p = p->next) {
00353       framein(p, out);
00354       if (out != f)
00355          ast_frfree(out);
00356       out = p->t->frameout(p);
00357    }
00358    if (consume)
00359       ast_frfree(f);
00360    if (out == NULL)
00361       return NULL;
00362    /* we have a frame, play with times */
00363    if (!ast_tvzero(delivery)) {
00364       /* Regenerate prediction after a discontinuity */
00365       if (ast_tvzero(path->nextout))
00366          path->nextout = ast_tvnow();
00367 
00368       /* Use next predicted outgoing timestamp */
00369       out->delivery = path->nextout;
00370       
00371       /* Predict next outgoing timestamp from samples in this
00372          frame. */
00373       path->nextout = ast_tvadd(path->nextout, ast_samp2tv(out->samples, ast_format_rate(out->subclass)));
00374    } else {
00375       out->delivery = ast_tv(0, 0);
00376       ast_set2_flag(out, has_timing_info, AST_FRFLAG_HAS_TIMING_INFO);
00377       if (has_timing_info) {
00378          out->ts = ts;
00379          out->len = len;
00380          out->seqno = seqno;
00381       }
00382    }
00383    /* Invalidate prediction if we're entering a silence period */
00384    if (out->frametype == AST_FRAME_CNG)
00385       path->nextout = ast_tv(0, 0);
00386    return out;
00387 }
00388 
00389 /*! \brief compute the cost of a single translation step */
00390 static void calc_cost(struct ast_translator *t, int seconds)
00391 {
00392    int num_samples = 0;
00393    struct ast_trans_pvt *pvt;
00394    struct timeval start;
00395    int cost;
00396    int out_rate = ast_format_rate(t->dstfmt);
00397 
00398    if (!seconds)
00399       seconds = 1;
00400    
00401    /* If they don't make samples, give them a terrible score */
00402    if (!t->sample) {
00403       ast_log(LOG_WARNING, "Translator '%s' does not produce sample frames.\n", t->name);
00404       t->cost = 99999;
00405       return;
00406    }
00407 
00408    pvt = newpvt(t);
00409    if (!pvt) {
00410       ast_log(LOG_WARNING, "Translator '%s' appears to be broken and will probably fail.\n", t->name);
00411       t->cost = 99999;
00412       return;
00413    }
00414 
00415    start = ast_tvnow();
00416 
00417    /* Call the encoder until we've processed the required number of samples */
00418    while (num_samples < seconds * out_rate) {
00419       struct ast_frame *f = t->sample();
00420       if (!f) {
00421          ast_log(LOG_WARNING, "Translator '%s' failed to produce a sample frame.\n", t->name);
00422          destroy(pvt);
00423          t->cost = 99999;
00424          return;
00425       }
00426       framein(pvt, f);
00427       ast_frfree(f);
00428       while ((f = t->frameout(pvt))) {
00429          num_samples += f->samples;
00430          ast_frfree(f);
00431       }
00432    }
00433 
00434    cost = ast_tvdiff_ms(ast_tvnow(), start);
00435 
00436    destroy(pvt);
00437 
00438    t->cost = cost / seconds;
00439 
00440    if (!t->cost)
00441       t->cost = 1;
00442 }
00443 
00444 /*!
00445  * \brief rebuild a translation matrix.
00446  * \note This function expects the list of translators to be locked
00447 */
00448 static void rebuild_matrix(int samples)
00449 {
00450    struct ast_translator *t;
00451    int x;      /* source format index */
00452    int y;      /* intermediate format index */
00453    int z;      /* destination format index */
00454 
00455    if (option_debug)
00456       ast_log(LOG_DEBUG, "Resetting translation matrix\n");
00457 
00458    bzero(tr_matrix, sizeof(tr_matrix));
00459 
00460    /* first, compute all direct costs */
00461    AST_LIST_TRAVERSE(&translators, t, list) {
00462       if (!t->active)
00463          continue;
00464 
00465       x = t->srcfmt;
00466       z = t->dstfmt;
00467 
00468       if (samples)
00469          calc_cost(t, samples);
00470      
00471       if (!tr_matrix[x][z].step || t->cost < tr_matrix[x][z].cost) {
00472          tr_matrix[x][z].step = t;
00473          tr_matrix[x][z].cost = t->cost;
00474       }
00475    }
00476 
00477    /*
00478     * For each triple x, y, z of distinct formats, check if there is
00479     * a path from x to z through y which is cheaper than what is
00480     * currently known, and in case, update the matrix.
00481     * Repeat until the matrix is stable.
00482     */
00483    for (;;) {
00484       int changed = 0;
00485       for (x = 0; x < MAX_FORMAT; x++) {      /* source format */
00486          for (y=0; y < MAX_FORMAT; y++) {    /* intermediate format */
00487             if (x == y)                     /* skip ourselves */
00488                continue;
00489 
00490             for (z=0; z<MAX_FORMAT; z++) {  /* dst format */
00491                int newcost;
00492 
00493                if (z == x || z == y)       /* skip null conversions */
00494                   continue;
00495                if (!tr_matrix[x][y].step)  /* no path from x to y */
00496                   continue;
00497                if (!tr_matrix[y][z].step)  /* no path from y to z */
00498                   continue;
00499                newcost = tr_matrix[x][y].cost + tr_matrix[y][z].cost;
00500                if (tr_matrix[x][z].step && newcost >= tr_matrix[x][z].cost)
00501                   continue;               /* x->y->z is more expensive than
00502                                            * the existing path */
00503                /* ok, we can get from x to z via y with a cost that
00504                   is the sum of the transition from x to y and
00505                   from y to z */
00506                    
00507                tr_matrix[x][z].step = tr_matrix[x][y].step;
00508                tr_matrix[x][z].cost = newcost;
00509                tr_matrix[x][z].multistep = 1;
00510                if (option_debug)
00511                   ast_log(LOG_DEBUG, "Discovered %d cost path from %s to %s, via %d\n", tr_matrix[x][z].cost, ast_getformatname(x), ast_getformatname(z), y);
00512                changed++;
00513             }
00514          }
00515       }
00516       if (!changed)
00517          break;
00518    }
00519 }
00520 
00521 /*! \brief CLI "show translation" command handler */
00522 static int show_translation_deprecated(int fd, int argc, char *argv[])
00523 {
00524 #define SHOW_TRANS 13
00525    int x, y, z;
00526    int curlen = 0, longest = 0;
00527 
00528    if (argc > 4) 
00529       return RESULT_SHOWUSAGE;
00530 
00531    AST_LIST_LOCK(&translators);  
00532    
00533    if (argv[2] && !strcasecmp(argv[2], "recalc")) {
00534       z = argv[3] ? atoi(argv[3]) : 1;
00535 
00536       if (z <= 0) {
00537          ast_cli(fd, "         C'mon let's be serious here... defaulting to 1.\n");
00538          z = 1;
00539       }
00540 
00541       if (z > MAX_RECALC) {
00542          ast_cli(fd, "         Maximum limit of recalc exceeded by %d, truncating value to %d\n", z - MAX_RECALC, MAX_RECALC);
00543          z = MAX_RECALC;
00544       }
00545       ast_cli(fd, "         Recalculating Codec Translation (number of sample seconds: %d)\n\n", z);
00546       rebuild_matrix(z);
00547    }
00548 
00549    ast_cli(fd, "         Translation times between formats (in milliseconds) for one second of data\n");
00550    ast_cli(fd, "          Source Format (Rows) Destination Format (Columns)\n\n");
00551    /* Get the length of the longest (usable?) codec name, so we know how wide the left side should be */
00552    for (x = 0; x < SHOW_TRANS; x++) {
00553       curlen = strlen(ast_getformatname(1 << (x)));
00554       if (curlen > longest)
00555          longest = curlen;
00556    }
00557    for (x = -1; x < SHOW_TRANS; x++) {
00558       char line[120];
00559       char *buf = line;
00560       size_t left = sizeof(line) - 1;  /* one initial space */
00561       /* next 2 lines run faster than using ast_build_string() */
00562       *buf++ = ' ';
00563       *buf = '\0';
00564       for (y = -1; y < SHOW_TRANS; y++) {
00565          if (y >= 0)
00566             curlen = strlen(ast_getformatname(1 << (y)));
00567 
00568          if (x >= 0 && y >= 0 && tr_matrix[x][y].step) {
00569             /* XXX 999 is a little hackish
00570                We don't want this number being larger than the shortest (or current) codec
00571                For now, that is "gsm" */
00572             ast_build_string(&buf, &left, "%*d", curlen + 1, tr_matrix[x][y].cost > 999 ? 0 : tr_matrix[x][y].cost);
00573          } else if (x == -1 && y >= 0) {
00574             /* Top row - use a dynamic size */
00575             ast_build_string(&buf, &left, "%*s", curlen + 1, ast_getformatname(1 << (y)) );
00576          } else if (y == -1 && x >= 0) {
00577             /* Left column - use a static size. */
00578             ast_build_string(&buf, &left, "%*s", longest, ast_getformatname(1 << (x)) );
00579          } else if (x >= 0 && y >= 0) {
00580             ast_build_string(&buf, &left, "%*s", curlen + 1, "-");
00581          } else {
00582             ast_build_string(&buf, &left, "%*s", longest, "");
00583          }
00584       }
00585       ast_build_string(&buf, &left, "\n");
00586       ast_cli(fd, line);         
00587    }
00588    AST_LIST_UNLOCK(&translators);
00589    return RESULT_SUCCESS;
00590 }
00591 
00592 static int show_translation(int fd, int argc, char *argv[])
00593 {
00594    int x, y, z;
00595    int curlen = 0, longest = 0;
00596 
00597    if (argc > 5)
00598       return RESULT_SHOWUSAGE;
00599 
00600    AST_LIST_LOCK(&translators);  
00601    
00602    if (argv[3] && !strcasecmp(argv[3], "recalc")) {
00603       z = argv[4] ? atoi(argv[4]) : 1;
00604 
00605       if (z <= 0) {
00606          ast_cli(fd, "         C'mon let's be serious here... defaulting to 1.\n");
00607          z = 1;
00608       }
00609 
00610       if (z > MAX_RECALC) {
00611          ast_cli(fd, "         Maximum limit of recalc exceeded by %d, truncating value to %d\n", z - MAX_RECALC, MAX_RECALC);
00612          z = MAX_RECALC;
00613       }
00614       ast_cli(fd, "         Recalculating Codec Translation (number of sample seconds: %d)\n\n", z);
00615       rebuild_matrix(z);
00616    }
00617 
00618    ast_cli(fd, "         Translation times between formats (in milliseconds) for one second of data\n");
00619    ast_cli(fd, "          Source Format (Rows) Destination Format (Columns)\n\n");
00620    /* Get the length of the longest (usable?) codec name, so we know how wide the left side should be */
00621    for (x = 0; x < SHOW_TRANS; x++) {
00622       curlen = strlen(ast_getformatname(1 << (x)));
00623       if (curlen > longest)
00624          longest = curlen;
00625    }
00626    for (x = -1; x < SHOW_TRANS; x++) {
00627       char line[120];
00628       char *buf = line;
00629       size_t left = sizeof(line) - 1;  /* one initial space */
00630       /* next 2 lines run faster than using ast_build_string() */
00631       *buf++ = ' ';
00632       *buf = '\0';
00633       for (y = -1; y < SHOW_TRANS; y++) {
00634          if (y >= 0)
00635             curlen = strlen(ast_getformatname(1 << (y)));
00636 
00637          if (x >= 0 && y >= 0 && tr_matrix[x][y].step) {
00638             /* XXX 999 is a little hackish
00639                We don't want this number being larger than the shortest (or current) codec
00640                For now, that is "gsm" */
00641             ast_build_string(&buf, &left, "%*d", curlen + 1, tr_matrix[x][y].cost > 999 ? 0 : tr_matrix[x][y].cost);
00642          } else if (x == -1 && y >= 0) {
00643             /* Top row - use a dynamic size */
00644             ast_build_string(&buf, &left, "%*s", curlen + 1, ast_getformatname(1 << (y)) );
00645          } else if (y == -1 && x >= 0) {
00646             /* Left column - use a static size. */
00647             ast_build_string(&buf, &left, "%*s", longest, ast_getformatname(1 << (x)) );
00648          } else if (x >= 0 && y >= 0) {
00649             ast_build_string(&buf, &left, "%*s", curlen + 1, "-");
00650          } else {
00651             ast_build_string(&buf, &left, "%*s", longest, "");
00652          }
00653       }
00654       ast_build_string(&buf, &left, "\n");
00655       ast_cli(fd, line);         
00656    }
00657    AST_LIST_UNLOCK(&translators);
00658    return RESULT_SUCCESS;
00659 }
00660 
00661 static char show_trans_usage[] =
00662 "Usage: core show translation [recalc] [<recalc seconds>]\n"
00663 "       Displays known codec translators and the cost associated\n"
00664 "with each conversion.  If the argument 'recalc' is supplied along\n"
00665 "with optional number of seconds to test a new test will be performed\n"
00666 "as the chart is being displayed.\n";
00667 
00668 static struct ast_cli_entry cli_show_translation_deprecated = {
00669    { "show", "translation", NULL },
00670    show_translation_deprecated, NULL,
00671    NULL };
00672 
00673 static struct ast_cli_entry cli_translate[] = {
00674    { { "core", "show", "translation", NULL },
00675    show_translation, "Display translation matrix",
00676    show_trans_usage, NULL, &cli_show_translation_deprecated },
00677 };
00678 
00679 /*! \brief register codec translator */
00680 int __ast_register_translator(struct ast_translator *t, struct ast_module *mod)
00681 {
00682    static int added_cli = 0;
00683    struct ast_translator *u;
00684 
00685    if (!mod) {
00686       ast_log(LOG_WARNING, "Missing module pointer, you need to supply one\n");
00687       return -1;
00688    }
00689 
00690    if (!t->buf_size) {
00691       ast_log(LOG_WARNING, "empty buf size, you need to supply one\n");
00692       return -1;
00693    }
00694 
00695    t->module = mod;
00696 
00697    t->srcfmt = powerof(t->srcfmt);
00698    t->dstfmt = powerof(t->dstfmt);
00699    t->active = 1;
00700 
00701    if (t->plc_samples) {
00702       if (t->buffer_samples < t->plc_samples) {
00703          ast_log(LOG_WARNING, "plc_samples %d buffer_samples %d\n",
00704             t->plc_samples, t->buffer_samples);
00705          return -1;
00706       }
00707       if (t->dstfmt != powerof(AST_FORMAT_SLINEAR))
00708          ast_log(LOG_WARNING, "plc_samples %d format %x\n",
00709             t->plc_samples, t->dstfmt);
00710    }
00711    if (t->srcfmt >= MAX_FORMAT) {
00712       ast_log(LOG_WARNING, "Source format %s is larger than MAX_FORMAT\n", ast_getformatname(t->srcfmt));
00713       return -1;
00714    }
00715 
00716    if (t->dstfmt >= MAX_FORMAT) {
00717       ast_log(LOG_WARNING, "Destination format %s is larger than MAX_FORMAT\n", ast_getformatname(t->dstfmt));
00718       return -1;
00719    }
00720 
00721    if (t->buf_size) {
00722                /*
00723       * Align buf_size properly, rounding up to the machine-specific
00724       * alignment for pointers.
00725       */
00726       struct _test_align { void *a, *b; } p;
00727       int align = (char *)&p.b - (char *)&p.a;
00728 
00729       t->buf_size = ((t->buf_size + align - 1) / align) * align;
00730    }
00731 
00732    if (t->frameout == NULL)
00733       t->frameout = default_frameout;
00734   
00735    calc_cost(t, 1);
00736 
00737    if (option_verbose > 1) {
00738       char tmp[80];
00739 
00740       ast_verbose(VERBOSE_PREFIX_2 "Registered translator '%s' from format %s to %s, cost %d\n",
00741              term_color(tmp, t->name, COLOR_MAGENTA, COLOR_BLACK, sizeof(tmp)),
00742              ast_getformatname(1 << t->srcfmt), ast_getformatname(1 << t->dstfmt), t->cost);
00743    }
00744 
00745    if (!added_cli) {
00746       ast_cli_register_multiple(cli_translate, sizeof(cli_translate) / sizeof(struct ast_cli_entry));
00747       added_cli++;
00748    }
00749 
00750    AST_LIST_LOCK(&translators);
00751 
00752    /* find any existing translators that provide this same srcfmt/dstfmt,
00753       and put this one in order based on cost */
00754    AST_LIST_TRAVERSE_SAFE_BEGIN(&translators, u, list) {
00755       if ((u->srcfmt == t->srcfmt) &&
00756           (u->dstfmt == t->dstfmt) &&
00757           (u->cost > t->cost)) {
00758          AST_LIST_INSERT_BEFORE_CURRENT(&translators, t, list);
00759          t = NULL;
00760       }
00761    }
00762    AST_LIST_TRAVERSE_SAFE_END;
00763 
00764    /* if no existing translator was found for this format combination,
00765       add it to the beginning of the list */
00766    if (t)
00767       AST_LIST_INSERT_HEAD(&translators, t, list);
00768 
00769    rebuild_matrix(0);
00770 
00771    AST_LIST_UNLOCK(&translators);
00772 
00773    return 0;
00774 }
00775 
00776 /*! \brief unregister codec translator */
00777 int ast_unregister_translator(struct ast_translator *t)
00778 {
00779    char tmp[80];
00780    struct ast_translator *u;
00781    int found = 0;
00782 
00783    AST_LIST_LOCK(&translators);
00784    AST_LIST_TRAVERSE_SAFE_BEGIN(&translators, u, list) {
00785       if (u == t) {
00786          AST_LIST_REMOVE_CURRENT(&translators, list);
00787          if (option_verbose > 1)
00788             ast_verbose(VERBOSE_PREFIX_2 "Unregistered translator '%s' from format %s to %s\n", term_color(tmp, t->name, COLOR_MAGENTA, COLOR_BLACK, sizeof(tmp)), ast_getformatname(1 << t->srcfmt), ast_getformatname(1 << t->dstfmt));
00789          found = 1;
00790          break;
00791       }
00792    }
00793    AST_LIST_TRAVERSE_SAFE_END;
00794 
00795    if (found)
00796       rebuild_matrix(0);
00797 
00798    AST_LIST_UNLOCK(&translators);
00799 
00800    return (u ? 0 : -1);
00801 }
00802 
00803 void ast_translator_activate(struct ast_translator *t)
00804 {
00805    AST_LIST_LOCK(&translators);
00806    t->active = 1;
00807    rebuild_matrix(0);
00808    AST_LIST_UNLOCK(&translators);
00809 }
00810 
00811 void ast_translator_deactivate(struct ast_translator *t)
00812 {
00813    AST_LIST_LOCK(&translators);
00814    t->active = 0;
00815    rebuild_matrix(0);
00816    AST_LIST_UNLOCK(&translators);
00817 }
00818 
00819 /*! \brief Calculate our best translator source format, given costs, and a desired destination */
00820 int ast_translator_best_choice(int *dst, int *srcs)
00821 {
00822    int x,y;
00823    int best = -1;
00824    int bestdst = 0;
00825    int cur, cursrc;
00826    int besttime = INT_MAX;
00827    int beststeps = INT_MAX;
00828    int common = ((*dst) & (*srcs)) & AST_FORMAT_AUDIO_MASK; /* are there common formats ? */
00829 
00830    if (common) { /* yes, pick one and return */
00831       for (cur = 1, y = 0; y <= MAX_AUDIO_FORMAT; cur <<= 1, y++) {
00832          if (cur & common) /* guaranteed to find one */
00833             break;
00834       }
00835       /* We are done, this is a common format to both. */
00836       *srcs = *dst = cur;
00837       return 0;
00838    } else { /* No, we will need to translate */
00839       AST_LIST_LOCK(&translators);
00840       for (cur = 1, y = 0; y <= MAX_AUDIO_FORMAT; cur <<= 1, y++) {
00841          if (! (cur & *dst))
00842             continue;
00843          for (cursrc = 1, x = 0; x <= MAX_AUDIO_FORMAT; cursrc <<= 1, x++) {
00844             if (!(*srcs & cursrc) || !tr_matrix[x][y].step ||
00845                 tr_matrix[x][y].cost >  besttime)
00846                continue;   /* not existing or no better */
00847             if (tr_matrix[x][y].cost < besttime ||
00848                 tr_matrix[x][y].multistep < beststeps) {
00849                /* better than what we have so far */
00850                best = cursrc;
00851                bestdst = cur;
00852                besttime = tr_matrix[x][y].cost;
00853                beststeps = tr_matrix[x][y].multistep;
00854             }
00855          }
00856       }
00857       AST_LIST_UNLOCK(&translators);
00858       if (best > -1) {
00859          *srcs = best;
00860          *dst = bestdst;
00861          best = 0;
00862       }
00863       return best;
00864    }
00865 }
00866 
00867 unsigned int ast_translate_path_steps(unsigned int dest, unsigned int src)
00868 {
00869    unsigned int res = -1;
00870 
00871    /* convert bitwise format numbers into array indices */
00872    src = powerof(src);
00873    dest = powerof(dest);
00874 
00875    AST_LIST_LOCK(&translators);
00876 
00877    if (tr_matrix[src][dest].step)
00878       res = tr_matrix[src][dest].multistep + 1;
00879 
00880    AST_LIST_UNLOCK(&translators);
00881 
00882    return res;
00883 }
00884 
00885 unsigned int ast_translate_available_formats(unsigned int dest, unsigned int src)
00886 {
00887    unsigned int res = dest;
00888    unsigned int x;
00889    unsigned int src_audio = src & AST_FORMAT_AUDIO_MASK;
00890    unsigned int src_video = src & AST_FORMAT_VIDEO_MASK;
00891 
00892    /* if we don't have a source format, we just have to try all
00893       possible destination formats */
00894    if (!src)
00895       return dest;
00896 
00897    /* If we have a source audio format, get its format index */
00898    if (src_audio)
00899       src_audio = powerof(src_audio);
00900 
00901    /* If we have a source video format, get its format index */
00902    if (src_video)
00903       src_video = powerof(src_video);
00904 
00905    AST_LIST_LOCK(&translators);
00906 
00907    /* For a given source audio format, traverse the list of
00908       known audio formats to determine whether there exists
00909       a translation path from the source format to the
00910       destination format. */
00911    for (x = 1; src_audio && x < AST_FORMAT_MAX_AUDIO; x <<= 1) {
00912       /* if this is not a desired format, nothing to do */
00913       if (!dest & x)
00914          continue;
00915 
00916       /* if the source is supplying this format, then
00917          we can leave it in the result */
00918       if (src & x)
00919          continue;
00920 
00921       /* if we don't have a translation path from the src
00922          to this format, remove it from the result */
00923       if (!tr_matrix[src_audio][powerof(x)].step) {
00924          res &= ~x;
00925          continue;
00926       }
00927 
00928       /* now check the opposite direction */
00929       if (!tr_matrix[powerof(x)][src_audio].step)
00930          res &= ~x;
00931    }
00932 
00933    /* For a given source video format, traverse the list of
00934       known video formats to determine whether there exists
00935       a translation path from the source format to the
00936       destination format. */
00937    for (; src_video && x < AST_FORMAT_MAX_VIDEO; x <<= 1) {
00938       /* if this is not a desired format, nothing to do */
00939       if (!dest & x)
00940          continue;
00941 
00942       /* if the source is supplying this format, then
00943          we can leave it in the result */
00944       if (src & x)
00945          continue;
00946 
00947       /* if we don't have a translation path from the src
00948          to this format, remove it from the result */
00949       if (!tr_matrix[src_video][powerof(x)].step) {
00950          res &= ~x;
00951          continue;
00952       }
00953 
00954       /* now check the opposite direction */
00955       if (!tr_matrix[powerof(x)][src_video].step)
00956          res &= ~x;
00957    }
00958 
00959    AST_LIST_UNLOCK(&translators);
00960 
00961    return res;
00962 }
00963 
00964 void ast_translate_frame_freed(struct ast_frame *fr)
00965 {
00966    struct ast_trans_pvt *pvt;
00967 
00968    ast_clear_flag(fr, AST_FRFLAG_FROM_TRANSLATOR);
00969 
00970    pvt = (struct ast_trans_pvt *) (((char *) fr) - offsetof(struct ast_trans_pvt, f));
00971 
00972    if (pvt->datalen != -1)
00973       return;
00974    
00975    destroy(pvt);
00976 }

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