/*
 * Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
 *                         University Research and Technology
 *                         Corporation.  All rights reserved.
 * Copyright (c) 2004-2005 The University of Tennessee and The University
 *                         of Tennessee Research Foundation.  All rights
 *                         reserved.
 * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart, 
 *                         University of Stuttgart.  All rights reserved.
 * Copyright (c) 2004-2005 The Regents of the University of California.
 *                         All rights reserved.
 * Copyright (c) 2006      Cisco Systems, Inc.  All rights reserved.
 * $COPYRIGHT$
 * 
 * Additional copyrights may follow
 * 
 * $HEADER$
 */

#include "ompi_config.h"

#include <string.h>
#include <ctype.h>
#include <stdlib.h>

#include "opal/util/output.h"
#include "opal/util/show_help.h"
#include "opal/mca/base/mca_base_param.h"

#include "btl_openib.h"
#include "btl_openib_lex.h"
#include "btl_openib_ini.h"

static const char *ini_filename = NULL;
static bool initialized = false;
static opal_list_t hcas;
static char *key_buffer = NULL;
static size_t key_buffer_len = 0;


/*
 * Struct to hold the section name, vendor ID, and list of vendor part
 * ID's and a corresponding set of values (parsed from an INI file).
 */
typedef struct parsed_section_values_t {
    char *name;

    uint32_t *vendor_ids;
    int vendor_ids_len;
    
    uint32_t *vendor_part_ids;
    int vendor_part_ids_len;

    ompi_btl_openib_ini_values_t values;
} parsed_section_values_t;

/*
 * Struct to hold the final values.   Different from above in a few ways:
 *
 * - The vendor and part IDs will always be set properly
 * - There will only be one part ID (i.e., the above struct is
 *   exploded into multiple of these for each of searching)
 * - There is a super of opal_list_item_t so that we can have a list
 *   of these
 */
typedef struct hca_values_t {
    opal_list_item_t super;

    char *section_name;
    uint32_t vendor_id;
    uint32_t vendor_part_id;

    ompi_btl_openib_ini_values_t values;
} hca_values_t;

static void hca_values_constructor(hca_values_t *s);
static void hca_values_destructor(hca_values_t *s);

OBJ_CLASS_INSTANCE(hca_values_t,
                   opal_list_item_t,
                   hca_values_constructor,
                   hca_values_destructor);


/*
 * Local functions
 */
static int parse_file(char *filename);
static int parse_line(parsed_section_values_t *item);
static void reset_section(bool had_previous_value, parsed_section_values_t *s);
static void reset_values(ompi_btl_openib_ini_values_t *v);
static int save_section(parsed_section_values_t *s);
static int intify(char *string);
static int intify_list(char *str, uint32_t **values, int *len);
static inline void show_help(const char *topic);


/*
 * Read the INI files for HCA-specific values and save them in
 * internal data structures for later lookup.
 */
int ompi_btl_openib_ini_init(void)
{
    int ret = OMPI_ERR_NOT_FOUND;
    char *colon;

    OBJ_CONSTRUCT(&hcas, opal_list_t);

    colon = strchr(mca_btl_openib_component.hca_params_file_names, ':');
    if (NULL == colon) {
        /* If we've only got 1 file (i.e., no colons found), parse it
           and be done */
        ret = parse_file(mca_btl_openib_component.hca_params_file_names);
    } else {
        /* Otherwise, loop over all the files and parse them */
        char *orig = strdup(mca_btl_openib_component.hca_params_file_names);
        char *str = orig;

        while (NULL != (colon = strchr(str, ':'))) {
            *colon = '\0';
            ret = parse_file(str);
            /* Note that NOT_FOUND and SUCCESS are not fatal errors
               and we keep going.  Other errors are treated as
               fatal */
            if (OMPI_ERR_NOT_FOUND != ret && OMPI_SUCCESS != ret) {
                break;
            }
            str = colon + 1;
        }
        /* Parse the last file if we didn't have a fatal error above */
        if (OMPI_ERR_NOT_FOUND != ret && OMPI_SUCCESS != ret) {
            ret = parse_file(str);
        }

        /* All done */
        free(orig);
    }

    /* Return SUCCESS unless we got a fatal error */

    initialized = true;
    return (OMPI_SUCCESS == ret || OMPI_ERR_NOT_FOUND == ret) ?
        OMPI_SUCCESS : ret;
}


/*
 * The component found an HCA and is querying to see if an INI file
 * specified any parameters for it.
 */
int ompi_btl_openib_ini_query(uint32_t vendor_id, uint32_t vendor_part_id,
                              ompi_btl_openib_ini_values_t *values)
{
    int ret;
    hca_values_t *h;
    opal_list_item_t *item;

    if (!initialized) {
        if (OMPI_SUCCESS != (ret = ompi_btl_openib_ini_init())) {
            return ret;
        }
    }

    if (mca_btl_openib_component.verbose) {
        BTL_OUTPUT(("Querying INI files for vendor 0x%04x, part ID %d", 
                    vendor_id, vendor_part_id));
    }

    reset_values(values);

    /* Iterate over all the saved hcas */
    for (item = opal_list_get_first(&hcas); 
         item != opal_list_get_end(&hcas);
         item = opal_list_get_next(item)) {
        h = (hca_values_t*) item;
        if (vendor_id == h->vendor_id &&
            vendor_part_id == h->vendor_part_id) {
            /* Found it! */
            *values = h->values;
            if (mca_btl_openib_component.verbose) {
                BTL_OUTPUT(("Found corresponding INI values: %s",
                            h->section_name));
            }
            return OMPI_SUCCESS;
        }
    }

    /* If we fall through to here, we didn't find it */
    if (mca_btl_openib_component.verbose) {
        BTL_OUTPUT(("Did not find corresponding INI values"));
    }
    return OMPI_ERR_NOT_FOUND;
}


/*
 * The component is shutting down; release all internal state
 */
int ompi_btl_openib_ini_finalize(void)
{
    opal_list_item_t *item;

    if (initialized) {
        for (item = opal_list_remove_first(&hcas);
             NULL != item;
             item = opal_list_remove_first(&hcas)) {
            OBJ_RELEASE(item);
        }
        OBJ_DESTRUCT(&hcas);
        initialized = true;
    }

    return OMPI_SUCCESS;
}

/**************************************************************************/

/*
 * Parse a single file
 */
static int parse_file(char *filename)
{
    int val;
    int ret = OMPI_SUCCESS;
    bool showed_no_section_warning = false;
    bool showed_unexpected_tokens_warning = false;
    parsed_section_values_t section;

    reset_section(false, &section);

    /* Open the file */
    ini_filename = filename;
    btl_openib_ini_yyin = fopen(filename, "r");
    if (NULL == btl_openib_ini_yyin) {
        opal_show_help("help-mpi-btl-openib.txt", "ini file:file not found",
                       true, filename);
        ret = OMPI_ERR_NOT_FOUND;
        goto cleanup;
    }

    /* Do the parsing */
    btl_openib_ini_parse_done = false;
    btl_openib_ini_yynewlines = 1;
    btl_openib_ini_init_buffer(btl_openib_ini_yyin);
    while (!btl_openib_ini_parse_done) {
        val = btl_openib_ini_yylex();
        switch (val) {
        case BTL_OPENIB_INI_PARSE_DONE:
            /* This will also set btl_openib_ini_parse_done to true, so just
               break here */
            break;

        case BTL_OPENIB_INI_PARSE_NEWLINE:
            /* blank line!  ignore it */
            break;

        case BTL_OPENIB_INI_PARSE_SECTION:
            /* We're starting a new section; if we have previously
               parsed a section, go see if we can use its values. */
            save_section(&section);

            reset_section(true, &section);
            section.name = strdup(btl_openib_ini_yytext);
            break;

        case BTL_OPENIB_INI_PARSE_SINGLE_WORD:
            if (NULL == section.name) {
                /* Warn that there is no current section, and ignore
                   this parameter */
                if (!showed_no_section_warning) {
                    show_help("ini file:not in a section");
                    showed_no_section_warning = true;
                }
                /* Parse it and then dump it */
                parse_line(&section);
                reset_section(true, &section);
            } else {
                parse_line(&section);
            }
            break;

        default:
            /* anything else is an error */
            if (!showed_unexpected_tokens_warning) {
                show_help("ini file:unexpected token");
                showed_unexpected_tokens_warning = true;
            }
            break;
        }
    }
    save_section(&section);
    fclose(btl_openib_ini_yyin);

cleanup:
    reset_section(true, &section);
    if (NULL != key_buffer) {
        free(key_buffer);
        key_buffer = NULL;
        key_buffer_len = 0;
    }
    return ret;
}


/*
 * Parse a single line in the INI file
 */
static int parse_line(parsed_section_values_t *sv)
{
    int val, ret = OMPI_SUCCESS;
    char *value = NULL;
    bool showed_unknown_field_warning = false;

    /* Save the name name */
    if (key_buffer_len < strlen(btl_openib_ini_yytext) + 1) {
        char *tmp;
        key_buffer_len = strlen(btl_openib_ini_yytext) + 1;
        tmp = realloc(key_buffer, key_buffer_len);
        if (NULL == tmp) {
            free(key_buffer);
            key_buffer_len = 0;
            key_buffer = NULL;
            return OMPI_ERR_TEMP_OUT_OF_RESOURCE;
        }
        key_buffer = tmp;
    }
    strncpy(key_buffer, btl_openib_ini_yytext, key_buffer_len);

    /* The first thing we have to see is an "=" */
    val = btl_openib_ini_yylex();
    if (btl_openib_ini_parse_done || BTL_OPENIB_INI_PARSE_EQUAL != val) {
        show_help("ini file:expected equals");
        return OMPI_ERROR;
    }

    /* Next we get the value */
    val = btl_openib_ini_yylex();
    if (BTL_OPENIB_INI_PARSE_SINGLE_WORD == val ||
        BTL_OPENIB_INI_PARSE_VALUE == val) {
        value = strdup(btl_openib_ini_yytext);

        /* Now we need to see the newline */
        val = btl_openib_ini_yylex();
        if (BTL_OPENIB_INI_PARSE_NEWLINE != val &&
            BTL_OPENIB_INI_PARSE_DONE != val) {
            show_help("ini file:expected newline");
            free(value);
            return OMPI_ERROR;
        }
    }

    /* If we did not get EOL or EOF, something is wrong */
    else if (BTL_OPENIB_INI_PARSE_DONE != val &&
             BTL_OPENIB_INI_PARSE_NEWLINE != val) {
        show_help("ini file:expected newline");
        return OMPI_ERROR;
    }

    /* Ok, we got a good parse.  Now figure out what it is and save
       the value.  Note that the flex already took care of trimming
       all whitespace at the beginning and ending of the value. */

    if (0 == strcasecmp(key_buffer, "vendor_id")) {
        if (OMPI_SUCCESS != (ret = intify_list(value, &sv->vendor_ids, 
                                               &sv->vendor_ids_len))) {
            return ret;
        }
    }

    else if (0 == strcasecmp(key_buffer, "vendor_part_id")) {
        if (OMPI_SUCCESS != (ret = intify_list(value, &sv->vendor_part_ids,
                                               &sv->vendor_part_ids_len))) {
            return ret;
        }
    }

    else if (0 == strcasecmp(key_buffer, "mtu")) {
        /* Single value */
        sv->values.mtu = (uint32_t) intify(value);
        sv->values.mtu_set = true;
    }

    else {
        /* Have no idea what this parameter is.  Not an error -- just
           ignore it */
        if (!showed_unknown_field_warning) {
            show_help("ini file:unknown field");
            showed_unknown_field_warning = true;
        }
    }

    /* All done */

    if(NULL != value)
        free(value);
    return ret;
}


/*
 * Construct an hca_values_t and set all of its values to known states
 */
static void hca_values_constructor(hca_values_t *s)
{
    s->section_name = NULL;
    s->vendor_id = 0;
    s->vendor_part_id = 0;
    reset_values(&s->values);
}


/*
 * Destruct an hca_values_t and free any memory that it has
 */
static void hca_values_destructor(hca_values_t *s)
{
    if (NULL != s->section_name) {
        free(s->section_name);
    }
}


/*
 * Reset a parsed section; free any memory that it may have had
 */
static void reset_section(bool had_previous_value, parsed_section_values_t *s)
{
    if (had_previous_value) {
        if (NULL != s->name) {
            free(s->name);
        }
        if (NULL != s->vendor_ids) {
            free(s->vendor_ids);
        }
        if (NULL != s->vendor_part_ids) {
            free(s->vendor_part_ids);
        }
    }

    s->name = NULL;
    s->vendor_ids = NULL;
    s->vendor_ids_len = 0;
    s->vendor_part_ids = NULL;
    s->vendor_part_ids_len = 0;

    reset_values(&s->values);
}


/*
 * Reset the values to known states
 */
static void reset_values(ompi_btl_openib_ini_values_t *v)
{
    v->mtu = 0;
    v->mtu_set = false;
}


/*
 * If we have a valid section, see if we have a matching section
 * somewhere (i.e., same vendor ID and vendor part ID).  If we do,
 * update the values.  If not, save the values in a new instance and
 * add it to the list.
 */
static int save_section(parsed_section_values_t *s)
{
    int i, j;
    opal_list_item_t *item;
    hca_values_t *h;
    bool found;

    /* Is the parsed section valid? */
    if (NULL == s->name || 0 == s->vendor_ids_len || 
        0 == s->vendor_part_ids_len) {
        return OMPI_ERR_BAD_PARAM;
    }

    /* Iterate over each of the vendor/part IDs in the parsed
       values */
    for (i = 0; i < s->vendor_ids_len; ++i) {
        for (j = 0; j < s->vendor_part_ids_len; ++j) {
            found = false;

            /* Iterate over all the saved hcas */
            for (item = opal_list_get_first(&hcas); 
                 item != opal_list_get_end(&hcas);
                 item = opal_list_get_next(item)) {
                h = (hca_values_t*) item;
                if (s->vendor_ids[i] == h->vendor_id &&
                    s->vendor_part_ids[j] == h->vendor_part_id) {
                    /* Found a match.  Update any newly-set values. */
                    if (s->values.mtu_set) {
                        h->values.mtu = s->values.mtu;
                        h->values.mtu_set = true;
                        found = true;
                        break;
                    }
                }
            }

            /* Did we find/update it in the exising list?  If not,
               create a new one. */
            if (!found) {
                h = OBJ_NEW(hca_values_t);
                h->section_name = strdup(s->name);
                h->vendor_id = s->vendor_ids[i];
                h->vendor_part_id = s->vendor_part_ids[j];
                h->values = s->values;
                opal_list_append(&hcas, &h->super);
            }
        }
    }

    /* All done */

    return OMPI_SUCCESS;
}


/*
 * Do string-to-integer conversion, for both hex and decimal numbers
 */
static int intify(char *str)
{
    while (isspace(*str)) {
        ++str;
    }

    /* If it's hex, use sscanf() */
    if (strlen(str) > 3 && 0 == strncasecmp("0x", str, 2)) {
        unsigned int i;
        sscanf(str, "%X", &i);
        return (int) i;
    }

    /* Nope -- just decimal, so use atoi() */
    return atoi(str);
}


/*
 * Take a comma-delimited list and infity them all
 */
static int intify_list(char *value, uint32_t **values, int *len)
{
    char *comma;
    char *str = value;

    *len = 0;
    
    /* Comma-delimited list of values */
    comma = strchr(str, ',');
    if (NULL == comma) {
        /* If we only got one value (i.e., no comma found), then
           just make an array of one value and save it */
        *values = malloc(sizeof(uint32_t));
        if (NULL == *values) {
            return OMPI_ERR_OUT_OF_RESOURCE;
        }
        *values[0] = (uint32_t) intify(str);
        *len = 1;
    } else {
        /* If we found a comma, loop over all the values.  Be a
           little clever in that we alwasy alloc enough space for
           an extra value so that when we exit the loop, we don't
           have to realloc again to get space for the last item. */
        do {
            *comma = '\0';
            *values = realloc(*values, sizeof(uint32_t) * (*len + 2));
            (*values)[*len] = (int32_t) intify(str);
            ++(*len);
            str = comma + 1;
            comma = strchr(str, ',');
        } while (NULL != comma);
        /* Get the last value (i.e., the value after the last
           comma, because it won't have been snarfed in the
           loop) */
        (*values)[*len] = (uint32_t) intify(str);
        ++(*len);
    }

    return OMPI_SUCCESS;
}

/*
 * Trival helper function
 */
static inline void show_help(const char *topic)
{
    opal_show_help("help-mpi-btl-openib.txt", topic, true,
                   ini_filename, btl_openib_ini_yynewlines,
                   btl_openib_ini_yytext);
}