[z180-stamp.git] / avr / env.c

/*
 * (C) Copyright 2014 Leo C. <erbl259-lmu@yahoo.de>
 *
 * SPDX-License-Identifier:     GPL-2.0
 */

#include "common.h"
#include <string.h>
#include <stdlib.h>
#include <stdbool.h>
#include <avr/eeprom.h>

#include "config.h"
#include "debug.h"
#include "xmalloc.h"
#include "crc.h"
#include "command.h"
#include "env.h"


#define ENV_SIZE        (CONFIG_ENV_SIZE - sizeof(uint16_t) -1)
#define ACTIVE_FLAG     1
#define OBSOLETE_FLAG   0

#define ENVLIST_DELETE  (1<<0)


/*
 * Default Environment
 */

#define DELIM           "\0"

const FLASH char default_env[] = {
        ENV_BAUDRATE      "=" "115200" DELIM
        ENV_BOOTDELAY     "=" "3" DELIM
        ENV_BOOTCMD               "=" "pin ${pins}; loadcpm3; go ${startaddress}" DELIM
        ENV_CPM3_SYSFILE  "=" CONFIG_CPM3_SYSFILE DELIM
        ENV_PINALIAS      "=" "0:PG5,1:PG4,2:PB4,3:PB5,4:PB6,5:PB7,"
                                                  "6:PG3,7:PG2,8:PG1,9:PG0,10:PE7" DELIM
        ENV_STARTADDRESS  "=" "0" DELIM
        "pins"                    "=" "2,8 low 9 high 3 2" DELIM
        DELIM
};


/* EEPROM storage */
typedef struct environment_s {
        uint16_t        crc;            /* CRC16 over data bytes        */
        uint8_t         flags;          /* active/obsolete flags        */
        char            data[ENV_SIZE]; /* Environment data             */
} env_t;


/* */
typedef struct env_item_s {
        char * envvar;
} env_item_t;


static uint8_t env_valid;
static env_item_t env_list[CONFIG_ENVVAR_MAX];
static int entrycount;


static
char env_get_char(uint16_t index)
{
        unsigned int off = CONFIG_ENV_OFFSET;
        char ret;

        switch (env_valid) {
        case 2:
                off += CONFIG_ENV_SIZE;
        case 1:
                ret = (char) eeprom_read_byte((const uint8_t *)off + index +
                                offsetof(env_t, data));
                break;

        default:
                ret = default_env[index];
        }

        return ret;
}


static const FLASH char *comp_key;

static
int comp_env_items(const void *m1, const void *m2)
{
        env_item_t *ep1 = (env_item_t *) m1;
        env_item_t *ep2 = (env_item_t *) m2;

        if (ep1 == NULL)
                return - strcmp_P(ep2->envvar, comp_key);
        else
                return strcmp(ep1->envvar, ep2->envvar);
}


env_item_t *envlist_search(const MEMX char *name)
{
#ifdef __MEMX
        if (__builtin_avr_flash_segment(name) != -1) {
                comp_key = name;
                return bsearch(0, env_list, entrycount,
                                sizeof(env_item_t), comp_env_items);
        } else {

                env_item_t e;
                e.envvar = (char *) name;

                return bsearch(&e, env_list, entrycount,
                                sizeof(env_item_t), comp_env_items);
        }
#else
        env_item_t e;
        e.envvar = (char *) name;

        return bsearch(&e, env_list, entrycount,
                                sizeof(env_item_t), comp_env_items);
#endif /* __MEMX */
}


static
env_item_t *envlist_enter(env_item_t *e)
{
        const size_t size = sizeof(env_item_t);
        env_item_t *ep;

        ep = bsearch(e, env_list, entrycount,
                        size, comp_env_items);

        if (ep == NULL) {
                if (entrycount < CONFIG_ENVVAR_MAX) {

                        env_list[entrycount++] = *e;
                        qsort(env_list, entrycount, size, comp_env_items);
                        ep = bsearch(e, env_list, entrycount,
                                                size, comp_env_items);
                }
        } else {
                free(ep->envvar);
                ep->envvar = e->envvar;
        }

        return ep;
}


static
int env_item_delete(env_item_t *ep)
{
        if (entrycount == 0)
                return -1;

        free(ep->envvar);

        entrycount--;
        size_t size = sizeof(env_item_t);
        memmove(ep, ep + 1, (env_list - ep)*size + entrycount*size);

        return 0;
}

static
int envlist_delete(const MEMX char *name)
{
        env_item_t *ep = envlist_search(name);

        if (ep != NULL)
                return env_item_delete(ep);

        return 1;
}



static
int envlist_import(uint8_t flags)
{
        uint16_t index;

        int len;
        env_item_t e;
        char *np, c;
        uint_fast8_t ef;

        if ((flags & ENVLIST_DELETE) != 0)
                while (entrycount != 0)
                        env_item_delete(&env_list[entrycount-1]);

        for (index = 0; env_get_char(index) != '\0'; ) {
                for (len = 0; env_get_char(index + len) != '\0'; ++len) {
                        if ((index + len) >= ENV_SIZE)
                                return -1;
                }

                np = (char *) xmalloc(len+1);
                if (np == NULL) {
                        printf_P(PSTR("## Can't malloc %d bytes\n"), len+1);
                        return 1;
                }
                e.envvar = np;
                ef = 0;
                while ((c = env_get_char(index++)) != '\0') {
                        if (!ef && (c == '=')) {
                                *np = '\0';
                                ef = 1;
                        } else
                                *np = c;
                        np++;
                }
                *np = '\0';
                envlist_enter(&e);
        }


        return 0;
}


static
uint16_t env_crc(uint16_t data_offset)
{
        uint16_t crc;
        uint16_t i;
        char c, c0;

        crc = 0xffff;
        c = 0xff;
        for (i = 0; !(c == 0 && c0 == 0) && i < ENV_SIZE; i++)
        {
                c0 = c;
                c = eeprom_read_byte((const uint8_t *) data_offset + i);
                crc = crc16(crc, c);
        }
        return crc ;
}


/**
 * return valid env
 */
static
int env_check_valid(void)
{
        const uint16_t offset[2] = {CONFIG_ENV_OFFSET,
                                    CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE};
        uint_fast8_t flags[2], crc_ok[2];
        int rc;

        /* read FLAGS */
        flags[0] = eeprom_read_byte ((uint8_t *) offset[0] +
                                offsetof(env_t, flags));
        flags[1] = eeprom_read_byte ((uint8_t *) offset[1] +
                                offsetof(env_t, flags));

        /* check CRC */
        crc_ok[0] = (
                eeprom_read_word((uint16_t *) offset[0] +
                                offsetof(env_t, crc))
                == env_crc(offset[0] + offsetof(env_t, data))
        );
        crc_ok[1] = (
                eeprom_read_word((uint16_t *) offset[1] +
                                offsetof(env_t, crc))
                == env_crc(offset[1] + offsetof(env_t, data))
        );

        if (!crc_ok[0] && !crc_ok[1]) {
                rc = 0;

        } else if (crc_ok[0] && !crc_ok[1]) {
                rc = 1;
        } else if (!crc_ok[0] && crc_ok[1]) {
                rc = 2;
        } else {
                /* both ok - check serial */
#if 1
                if      (flags[1] == ACTIVE_FLAG && flags[0] != ACTIVE_FLAG)
                        rc = 2;
                else if (flags[1] == OBSOLETE_FLAG && flags[0] == 0xFF)
                        rc = 2;
                else
                        rc = 1;
#else
                if (flags[0] == ACTIVE_FLAG && flags[1] == OBSOLETE_FLAG)
                        rc = 1;
                else if (flags[0] == OBSOLETE_FLAG && flags[1] == ACTIVE_FLAG)
                        rc = 2;
                else if (flags[0] == 0xFF && flags[1] == 0)
                        rc = 2;
                else if (flags[1] == 0xFF && flags[0] == 0)
                        rc = 1;
                else /* flags are equal - almost impossible */
                        rc = 1;
#endif
        }

        return rc;
}


int env_init(void)
{
        env_valid = env_check_valid();
        if (env_valid == 0) {
                printf_P(PSTR("*** Warning - bad CRC, "
                                "using default environment\n\n"));
        }

        envlist_import(ENVLIST_DELETE);
        return 0;
}


char *getenv_str(const MEMX char *name)
{
        env_item_t *ep;
        char *ret = NULL;

        ep = envlist_search(name);
        if (ep != NULL)
                ret = ep->envvar + strlen(ep->envvar) +1;
        return ret;
}

static
int env_item_save(env_item_t *ep, uint16_t offset, int space_left)
{
        int nlen, vlen;
        char *var = ep->envvar;

        nlen = strlen(var);
        if (nlen == 0)
                return 0;
        vlen = strlen(var + nlen + 1);
        if (vlen == 0)
                return 0;
        if (nlen + vlen + 2 > space_left)
                return 0;

        eeprom_update_block(var, (uint8_t *) offset, nlen);
        offset += nlen;
        eeprom_update_byte((uint8_t *) offset++, '=');
        eeprom_update_block(var + nlen +1, (uint8_t *) offset, vlen+1);

        return nlen + vlen + 2;
}


static
int saveenv(void)
{
        unsigned int off     = CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE;
        unsigned int off_red = CONFIG_ENV_OFFSET;
        unsigned int pos;
        int len, left;
        uint16_t crc;
        int rc = 0;

        if (env_valid == 2) {
                off     = CONFIG_ENV_OFFSET;
                off_red = CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE;
        }

        eeprom_update_byte((uint8_t *) off + offsetof(env_t, flags), 0xff);

        pos = off + offsetof(env_t, data);
        left = ENV_SIZE - 1;
        for (int i = 0 ; i < entrycount; i++) {
                len = env_item_save(&env_list[i], pos, left);
                if (len == 0) {
                        return 1;
                }
                pos += len;
                left -= len;
        }
        /* terminate list */
        eeprom_update_byte((uint8_t *) pos, 0);
        crc = env_crc(off + offsetof(env_t, data));
        eeprom_update_word((uint16_t *) off + offsetof(env_t, crc), crc);
        eeprom_update_byte((uint8_t *) off + offsetof(env_t, flags),
                                        ACTIVE_FLAG);

        if (rc == 0) {
                eeprom_update_byte((uint8_t *) off_red + offsetof(env_t, flags),
                                        OBSOLETE_FLAG);
                env_valid = (env_valid == 2) ? 1 : 2;
        }

        return rc;
}


static
int env_item_print(env_item_t *ep, bool mode)
{
        int len;
        char *ev = ep->envvar;

        if (mode) {
                len = printf_P(PSTR("setenv %s "), ev) - 7;
                len += printf_P(PSTR("'%s'\n"), ev + len) - 2;
        } else {
        len = printf_P(PSTR("%s="), ev);
        len += printf_P(PSTR("%s\n"), ev + len);
        }
        return len;
}


/*
 * Command interface: print one or all environment variables
 *
 * Returns -1 in case of error, or length of printed string
 */
static
int env_print(const MEMX char *name, bool mode)
{
        int len = -1;

        if (name) {             /* print a single name */

                env_item_t *ep = envlist_search(name);
                if (ep != NULL)
                        len = env_item_print(ep, mode);

        } else {                /* print whole list */
                len = 0;
                for (int i = 0 ; i < entrycount; i++) {
                        len += env_item_print(&env_list[i], mode);
                }
        }
        return len;
}


/**
 * Set or delete environment variable
 *
 * Set a new environment variable,
 * or replace or delete an existing one.
 *
 * @param flag          (not used)
 * @param argc
 * @param argv[1]       Environment variable to set or delete
 *                      if no more args
 * @param argv[2] ...   Value to set it to
 *
 * @return 0 if ok, 1 on error
 */
static
command_ret_t _do_env_set(int flag, int argc, char * const argv[])
{
        int i, len;
        char *name, *value, *valp, *p;
        env_item_t e, *ep;

        (void) flag;

        name = argv[1];
        value = argv[2];

        if (strchr(name, '=')) {
                printf_P(PSTR("## Error: illegal character '='"
                       "in variable name \"%s\"\n"), name);
                return CMD_RET_FAILURE;
        }
        len = strlen(name);
        if (len > CONFIG_SYS_ENV_NAMELEN) {
                printf_P(PSTR("## Error: Variable name \"%s\" too long. "
                       "(max %d characters)\n"), name, CONFIG_SYS_ENV_NAMELEN);
                return CMD_RET_FAILURE;
        }
/*
        env_id++;
*/
        /* Delete only ? */
        if (argc < 3 || argv[2] == NULL) {
                int rc = envlist_delete(name);
                return rc ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
        }

        /*
         * Insert / replace new value
         */
        for (i = 2, len += 1; i < argc; ++i)
                len += strlen(argv[i]) + 1;

        value = xmalloc(len);
        if (value == NULL) {
                printf_P(PSTR("## Can't malloc %d bytes\n"), len);
                return CMD_RET_FAILURE;
        }
        strcpy(value, name);
        valp = value + strlen(name) + 1;
        for (i = 2, p = valp; i < argc; ++i) {
                char *v = argv[i];

                while ((*p++ = *v++) != '\0')
                        ;
                *(p - 1) = ' ';
        }
        if (p != valp)
                *--p = '\0';

        e.envvar = value;
        ep = envlist_enter(&e);
        if (!ep) {
                printf_P(PSTR("## Error inserting \"%s\" variable.\n"),
                        name);
                return CMD_RET_FAILURE;
        }

        return CMD_RET_SUCCESS;
}

/**
 * Set an environment variable
 *
 * @param varname       Environment variable to set
 * @param varvalue      Value to set it to
 * @return 0 if ok, 1 on error
 */
static
int setenv(const MEMX char *varname, const char *varvalue)
{
        int rc;

#ifdef __MEMX
        char *tmpname = NULL;
        if (__builtin_avr_flash_segment(varname) != -1) {
                tmpname = malloc(strlen_P(varname)+1);
                if (tmpname == NULL) {
                        printf_P(PSTR("setenv: Out of Memory!\n"));
                        return 1;
                }
                strcpy_P(tmpname, varname);
        } else
                tmpname = (char *) varname;
#endif

        const char * const argv[3] = { NULL, tmpname, varvalue };
        int argc = 3;

        if (varvalue == NULL || varvalue[0] == '\0')
                --argc;

        rc = (int) _do_env_set(0, argc, (char * const *)argv);

#ifdef __MEMX
        free(tmpname);
#endif
        return rc;
}

/**
 * Set an environment variable to an integer value
 *
 * @param name  Environment variable to set
 * @param value Value to set it to
 * @param radix Base
 * @return 0 if ok, 1 on error
 */
static
int setenv_intval(const MEMX char *name, unsigned long value, int radix)
{
        char buf[11];

        ultoa(value, buf, radix);

        return setenv(name, buf);
}

/**
 * Set an environment variable to a decimal integer value
 *
 * @param name  Environment variable to set
 * @param value Value to set it to
 * @return 0 if ok, 1 on error
 */
int setenv_ulong(const MEMX char *name, unsigned long value)
{
        return setenv_intval(name, value, 10);
}


/**
 * Set an environment variable to a value in hex
 *
 * @param name  Environment variable to set
 * @param value Value to set it to
 * @return 0 if ok, 1 on error
 */
int setenv_hex(const MEMX char *name, unsigned long value)
{
        return setenv_intval(name, value, 16);
}


/**
 * Decode the integer value of an environment variable and return it.
 *
 * @param name          Name of environemnt variable
 * @param base          Number base to use (normally 10, or 16 for hex)
 * @param default_val   Default value to return if the variable is not
 *                      found
 * @return the decoded value, or default_val if not found
 */
unsigned long getenv_ulong(const MEMX char *name, int base, unsigned long default_val)
{
        unsigned long value;
        char *vp, *endp;

        env_item_t *ep = envlist_search(name);

        if (ep != NULL ) {
                vp = ep->envvar + strlen(ep->envvar) +1;
                value = strtoul(vp, &endp, base);
                if (endp != vp)
                        return value;
        }

        return default_val;
}


/*
 * Read an environment variable as a boolean
 */
bool getenv_yesno(const MEMX char *name)
{
        char *s = getenv_str(name);

        if (s == NULL)
                return false;

        return strchr_P(PSTR("1yYtT"), *s) != NULL;

/*
        return *s == '1' || *s == 'y' || *s == 'Y' || *s == 't' || *s == 'T' ?
                1 : 0;
*/
}

command_ret_t do_env_print(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
        (void) cmdtp; (void) flag;

        bool mode = 0;
        command_ret_t rc = CMD_RET_SUCCESS;

        /* reset getopt() */
        optind = 0;

        int opt;
        while ((opt = getopt(argc, argv, PSTR("s"))) != -1) {
                switch (opt) {
                case 's':
                        mode = 1;
                        break;
                default: /* '?' */
                        return CMD_RET_USAGE;
                }
        }

        if (optind == argc) {
                /* print all env vars */
                int size = env_print(NULL, mode);
                if (size < 0)
                        return CMD_RET_FAILURE;
                if (mode == 0)
                        printf_P(PSTR("\nEnvironment size: %d/%d bytes\n"),
                                size, ENV_SIZE);
                return CMD_RET_SUCCESS;
        }

        /* print selected env vars */
        while (optind < argc) {
                int rc = env_print(argv[optind], mode);
                if (rc < 0) {
                        printf_P(PSTR("## Error: \"%s\" not defined\n"), argv[optind]);
                        rc = CMD_RET_FAILURE;
                }
                optind++;
        }

        return rc;
}


command_ret_t do_env_set(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
        (void) cmdtp;

        if (argc < 2)
                return CMD_RET_USAGE;

        return _do_env_set(flag, argc, argv);
}


command_ret_t do_env_default(cmd_tbl_t *cmdtp, int flag,
                          int argc, char * const argv[])
{
        (void) cmdtp; (void) flag; (void) argc; (void) argv;

        uint8_t tmp = env_valid;
        env_valid = 0;

        /* Reset the whole environment */
        printf_P(PSTR("## Resetting to default environment\n"));
        envlist_import(ENVLIST_DELETE);

        env_valid = tmp;

        return CMD_RET_SUCCESS;
}


command_ret_t do_env_save(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
        (void) cmdtp; (void) flag; (void) argc; (void) argv;

        printf_P(PSTR("Saving Environment ...\n"));
        return saveenv() ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
}


#if defined(CONFIG_AUTO_COMPLETE)
int env_complete(char *var, int maxv, char *cmdv[], int bufsz, char *buf)
{
        ENTRY *match;
        int found, idx;

        idx = 0;
        found = 0;
        cmdv[0] = NULL;

        while ((idx = hmatch_r(var, idx, &match, &env_htab))) {
                int vallen = strlen(match->key) + 1;

                if (found >= maxv - 2 || bufsz < vallen)
                        break;

                cmdv[found++] = buf;
                memcpy(buf, match->key, vallen);
                buf += vallen;
                bufsz -= vallen;
        }

        qsort(cmdv, found, sizeof(cmdv[0]), strcmp_compar);

        if (idx)
                cmdv[found++] = "...";

        cmdv[found] = NULL;
        return found;
}
#endif