Return to fifo_k.c CVS log

Up to [MW Coherent from dump] / coherent / d / conf / tboot

Annotation of coherent/d/conf/tboot/fifo_k.c, revision 1.1

1.1     ! root        1: /*
        !             2:  * fifo_k.c -- Routines for reading interally typed fifos.
        !             3:  * These are all that need to be included in the kernel.
        !             4:  */
        !             5: #include <sys/typed.h>
        !             6: 
        !             7: #ifdef KERNEL
        !             8: /* The input channel from tboot to the kernel.  */
        !             9: TYPED_SPACE(boot_gift, 512, T_FIFO_SIC);
        !            10: #endif
        !            11: 
        !            12: /* Read a typed space from a fifo.
        !            13:  * Return a pointer to the next typed space in the fifo ffp.  Returns
        !            14:  * NULL on end of fifo.
        !            15:  *
        !            16:  * This read assumes that ffp->f_space has type T_FIFO_SIC.
        !            17:  */
        !            18: typed_space *
        !            19: fifo_read(ffp)
        !            20:        register FIFO *ffp;
        !            21: {
        !            22:        typed_space *retval;
        !            23: 
        !            24:        /* Read MUST be set.  */
        !            25:        if (F_READ != F_READ & ffp->f_flags ) {
        !            26:                return(T_NULL);  /* This ffp is not open for reading.  */
        !            27:        }
        !            28: 
        !            29:        /* From here to the end of fifo_read is really fifo_read_sic().  */
        !            30: 
        !            31: 
        !            32:        /* Space of size 0 marks EOFIFO.  */
        !            33:        if ((int32)0 == ffp->f_offset->ts_size) {
        !            34:                retval = T_NULL;
        !            35:        } else {
        !            36:                /* Return the next space.  */
        !            37:                retval = ffp->f_offset;
        !            38:                /* Advance to the next space.  */
        !            39:                (char *) ffp->f_offset += ffp->f_offset->ts_size;
        !            40:        }
        !            41: 
        !            42:        return(retval);
        !            43: } /* fifo_read() */
        !            44: 
        !            45: /* Go back to the start of the fifo.
        !            46:  * Takes a FIFO.  For reading, go back to the first space; for writing
        !            47:  * truncate the FIFO to empty.
        !            48:  * Returns 1 on success, 0 otherwise.
        !            49:  */
        !            50: int
        !            51: fifo_rewind(ffp)
        !            52:        FIFO *ffp;
        !            53: {
        !            54:        /* Error checking of arguments.  */
        !            55:        if (0 == ffp->f_flags) {
        !            56:                return(0);      /* This ffp is not open.  */
        !            57:        }
        !            58: 
        !            59:        /* Either reading or writing MUST be set.  */
        !            60:        if ((F_READ != F_READ & ffp->f_flags) &&
        !            61:            (F_WRITE != F_WRITE & ffp->f_flags) ){
        !            62:                return(0);      /* Illegal flags.  */
        !            63:        }
        !            64: 
        !            65:        /* Rewind to the first space in this fifo (skip the header).  */
        !            66:        ffp->f_offset = ((typed_space *) (ffp->f_space)) + 1;
        !            67: 
        !            68:        return(1);
        !            69: } /* fifo_rewind() */
        !            70: 
        !            71: /* Finish with using a typed space as a fifo.
        !            72:  * Free up FIFO structure associated with a typed space.
        !            73:  * Returns 0 if ffp was not open, 1 otherwise.
        !            74:  */
        !            75: int
        !            76: fifo_close(ffp)
        !            77:        FIFO *ffp;
        !            78: {
        !            79:        if (0 == ffp->f_flags) {
        !            80:                return(0);      /* This ffp is not open.  */
        !            81:        }
        !            82:        ffp->f_space = F_NULL;
        !            83:        ffp->f_offset = T_NULL;
        !            84:        ffp->f_flags = 0;
        !            85: 
        !            86:        return(1);
        !            87: } /* fifo_close() */
        !            88: 
        !            89: /* Open a typed space as a fifo.
        !            90:  *
        !            91:  * Takes a typed_space that is already allocated, and a mode.    The type of
        !            92:  * the typed space must be a FIFO.  Only T_FIFO_SIC has been implimented
        !            93:  * (static, in-core fifo).
        !            94:  *
        !            95:  * The mode indicates whether to open for reading or writing.
        !            96:  *  mode == 0 means read only.
        !            97:  *  mode == 1 means write only.
        !            98:  *  Other values are illegal.
        !            99:  *
        !           100:  * Returns a pointer to an initialized FIFO structure.  FIFO structures are
        !           101:  * allocated from a pre-allocated array.  Returns F_NULL if it can't open
        !           102:  * the fifo.
        !           103:  */
        !           104: FIFO *
        !           105: fifo_open(fifo_space, mode)
        !           106:        typed_space *fifo_space;
        !           107:        int mode;
        !           108: {
        !           109:        /* ff_table is a table of FIFO structures which can be allocated on
        !           110:         * demand.  It is functionally similiar to the file descritor table
        !           111:         * in the kernel.
        !           112:         */
        !           113:        static FIFO ff_table[NFIFOS];
        !           114:        static int inited = (1==2);     /* Has ff_table been initialized?  */
        !           115: 
        !           116:        int i;          /* A handy counter.  */
        !           117:        FIFO *the_fifo; /* The fifo we are going to allocate.  */
        !           118: 
        !           119:        /* Initilize ff_table the first time we get called.  */
        !           120:        if (!inited) {
        !           121:                for (i = 0; i < NFIFOS; ++i) {
        !           122:                        ff_table[i].f_space = F_NULL;
        !           123:                        ff_table[i].f_flags = 0;
        !           124:                }
        !           125:                inited = (1==1);
        !           126:        }
        !           127: 
        !           128:        /* Check the type of the space we were passed.  */
        !           129:        switch (fifo_space->ts_type) {
        !           130:        case T_FIFO:    /* Overly general type, assuming SIC.  */
        !           131:                fifo_space->ts_type = T_FIFO_SIC;
        !           132:                break;
        !           133:        case T_FIFO_SIC:/* Static In-core Fifo.  */
        !           134:                break;
        !           135:        case T_FIFO_DIC:/* Dynamic In-core Fifo (can grow).  */
        !           136:                return(F_NULL); /* Unimplimented.  */
        !           137:        case T_FIFO_SP: /* Static Permanent Fifo (fixed size file). */
        !           138:                return(F_NULL); /* Unimplimented.  */
        !           139:        case T_FIFO_DP: /* Dynamic Permanent Fifo (ordinary file).  */
        !           140:                return(F_NULL); /* Unimplimented.  */
        !           141:        default:
        !           142:                return(F_NULL); /* Illegal type encountered.  */
        !           143:        }
        !           144: 
        !           145: 
        !           146:        /* Is this space at least big enough for an empty fifo?  */
        !           147:        if (fifo_space->ts_size < 2 * (sizeof(typed_space))) {
        !           148:                return(F_NULL);
        !           149:        }
        !           150: 
        !           151:        /* ASSERTION: fifo_space is a valid and implimented FIFO.  */
        !           152: 
        !           153:        /* Find the first free FIFO structure.  */
        !           154: 
        !           155:        /* This should be re-implimented using a malloc-based scheme.
        !           156:         * At the moment, the tertiary boot libraries do not include a
        !           157:         * malloc.
        !           158:         */
        !           159:        for (i = 0; (i < NFIFOS) && (0 != ff_table[i].f_flags); ++i) {
        !           160:                /* Do nothing else.  */
        !           161:        }
        !           162: 
        !           163:        if (NFIFOS == i) {
        !           164:                return(F_NULL); /* No more free fifo structs.  */
        !           165:        }
        !           166: 
        !           167:        the_fifo = &(ff_table[i]);
        !           168: 
        !           169:        /* ASSERTION: the_fifo points at a FIFO we can take.  */
        !           170: 
        !           171:        /* Initialize the FIFO struct.  */
        !           172:        the_fifo->f_space = fifo_space;
        !           173:        the_fifo->f_offset = fifo_space->ts_data;
        !           174: 
        !           175:        /* Note that an open for write does not truncate.  */
        !           176: 
        !           177:        /* Initilize the flags.  */
        !           178:        switch(mode) {
        !           179:        case 0: /* read */
        !           180:                the_fifo->f_flags |= F_READ;
        !           181:                break;
        !           182:        case 1: /* write */
        !           183:                the_fifo->f_flags |= F_WRITE;
        !           184:                break;
        !           185:        default:
        !           186:                return(F_NULL); /* Illegal mode flag.  */
        !           187:        }
        !           188:                
        !           189:        return(the_fifo);
        !           190: } /* fifo_open() */
        !           191: 
        !           192: 
        !           193: #ifdef TEST
        !           194: #include <stdio.h>
        !           195: 
        !           196: /* This is the typed space we will use for our FIFO operations.  */
        !           197: TYPED_SPACE(global_space, 128, T_FIFO_SIC);    /* Static In-Core Fifo.  */
        !           198: 
        !           199: int
        !           200: main()
        !           201: {
        !           202:        FIFO *ffp;              /* Fifo pointer for a handle.  */
        !           203:        char line[1024];        /* Place to put input lines.  */
        !           204:        long size;              /* Length for line.  (Sizes are all long.)  */
        !           205:        int i;
        !           206: 
        !           207:        typed_space *local_space;
        !           208: 
        !           209:        /* Open the fifo for writing.  */
        !           210:        if (F_NULL == (ffp = fifo_open(&global_space, 1))) {
        !           211:                fprintf(stderr, "Can't open global_space for writing.\n");
        !           212:                exit(1);
        !           213:        }
        !           214: 
        !           215:        do {
        !           216:                printf("Feed me: ");
        !           217:                gets(line);
        !           218:                size = (int32) (strlen(line) + 1);
        !           219:        } while (T_NULL != fifo_write_untyped(ffp, line, size, T_STR_STR));
        !           220: 
        !           221:        if (0 == fifo_close(ffp)) {
        !           222:                fprintf(stderr, "Failed to close global_space.\n");
        !           223:                exit(1);
        !           224:        }
        !           225: 
        !           226:        printf("OK, global_space is now full.\n");
        !           227:        /* ASSERTION: We've filled global_space with strings.  */
        !           228: 
        !           229:        /* Open the fifo for reading.  */
        !           230:        if (F_NULL == (ffp = fifo_open(&global_space, 0))) {
        !           231:                fprintf(stderr, "Can't open global_space for reading.\n");
        !           232:                exit(1);
        !           233:        }
        !           234: 
        !           235:        /* Dump the contents of this FIFO.  */
        !           236:        for (i = 1; T_NULL != (local_space = fifo_read(ffp)); ++i) {
        !           237:                printf("%d: size: %ld: type: 0x%x\n", i,
        !           238:                        local_space->ts_size,
        !           239:                        local_space->ts_type);
        !           240: 
        !           241:                /* Assume everything is a NUL terminated string.  */
        !           242:                printf("datum: %s\n\n", local_space->ts_data);
        !           243:                printf("Hit <RETURN>");
        !           244:                gets(line);
        !           245:        }
        !           246: 
        !           247: 
        !           248:        /* Rewind the file, and dump it out again.  */
        !           249:        printf("Rewinding.\n");
        !           250:        if (0 == fifo_rewind(ffp)) {
        !           251:                fprintf("Can't rewind global_space.\n");
        !           252:                exit(1);
        !           253:        }
        !           254: 
        !           255:        for (i = 1; T_NULL != (local_space = fifo_read(ffp)); ++i) {
        !           256:                printf("%d: size: %ld: type: 0x%x\n", i,
        !           257:                        local_space->ts_size,
        !           258:                        local_space->ts_type);
        !           259: 
        !           260:                /* Assume everything is a NUL terminated string.  */
        !           261:                printf("datum: %s\n\n", local_space->ts_data);
        !           262:        }
        !           263: 
        !           264:        if (0 == fifo_close(ffp)) {
        !           265:                fprintf(stderr, "Failed to close global_space.\n");
        !           266:                exit(1);
        !           267:        }
        !           268: 
        !           269:        exit(0);
        !           270: } /* main() */
        !           271: 
        !           272: #endif /* TEST */

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.