#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <sysparam.h>
#include <espressif/spi_flash.h>
//TODO: make this properly threadsafe
//TODO: reduce stack usage
//FIXME: CRC calculations/checking
/* The "magic" values that indicate the start of a sysparam region in flash.
* Note that SYSPARAM_STALE_MAGIC is written over SYSPARAM_ACTIVE_MAGIC, so it
* must not contain any set bits which are not set in SYSPARAM_ACTIVE_MAGIC
* (that is, going from SYSPARAM_ACTIVE_MAGIC to SYSPARAM_STALE_MAGIC must only
* clear bits, not set them)
*/
#define SYSPARAM_ACTIVE_MAGIC 0x70524f45 // "EORp" in little-endian
#define SYSPARAM_STALE_MAGIC 0x40524f45 // "EOR@" in little-endian
/* The size of the initial buffer created by sysparam_iter_start, etc, to hold
* returned key-value pairs. Setting this too small may result in a lot of
* unnecessary reallocs. Setting it too large will waste memory when iterating
* through entries.
*/
#define DEFAULT_ITER_BUF_SIZE 64
/* The size of the buffer (in words) used by `sysparam_create_area` when
* scanning a potential area to make sure it's currently empty. Note that this
* space is taken from the stack, so it should not be too large.
*/
#define SCAN_BUFFER_SIZE 8 // words
/* Size of region/entry headers. These should not normally need tweaking (and
* will probably require some code changes if they are tweaked).
*/
#define REGION_HEADER_SIZE 4 // NOTE: Must be multiple of 4
#define ENTRY_HEADER_SIZE 4 // NOTE: Must be multiple of 4
/* Maximum value that can be used for a key_id. This is limited by the format
* to 0x7e (0x7f would produce a corresponding value ID of 0xff, which is
* invalid)
*/
#define MAX_KEY_ID 0x7e
#ifndef SYSPARAM_DEBUG
#define SYSPARAM_DEBUG 0
#endif
/******************************* Useful Macros *******************************/
#define ROUND_TO_WORD_BOUNDARY(x) (((x) + 3) & 0xfffffffc)
#define ENTRY_SIZE(payload_len) (ENTRY_HEADER_SIZE + ROUND_TO_WORD_BOUNDARY(payload_len))
#define max(x, y) ((x) > (y) ? (x) : (y))
#define min(x, y) ((x) < (y) ? (x) : (y))
#define debug(level, format, ...) if (SYSPARAM_DEBUG >= (level)) { printf("%s" format "\n", "sysparam: ", ## __VA_ARGS__); }
#define CHECK_FLASH_OP(x) do { int __x = (x); if ((__x) != SPI_FLASH_RESULT_OK) { debug(1, "FLASH ERR: %d", __x); return SYSPARAM_ERR_IO; } } while (0);
/********************* Internal datatypes and structures *********************/
struct entry_header {
uint8_t prev_len;
uint8_t len;
uint8_t id;
uint8_t crc;
} __attribute__ ((packed));
struct sysparam_context {
uint32_t addr;
struct entry_header entry;
uint64_t unused_keys[2];
size_t compactable;
uint8_t max_key_id;
};
/*************************** Global variables/data ***************************/
static struct {
uint32_t cur_base;
uint32_t alt_base;
uint32_t end_addr;
size_t region_size;
} _sysparam_info;
/***************************** Internal routines *****************************/
/** Erase the sectors of a region */
static sysparam_status_t _format_region(uint32_t addr) {
uint16_t sector = addr / sdk_flashchip.sector_size;
int i;
for (i = 0; i < SYSPARAM_REGION_SECTORS; i++) {
CHECK_FLASH_OP(sdk_spi_flash_erase_sector(sector + i));
}
return SYSPARAM_OK;
}
/** Write the magic value at the beginning of a region */
static inline sysparam_status_t _write_region_header(uint32_t addr, bool active) {
uint32_t magic = active ? SYSPARAM_ACTIVE_MAGIC : SYSPARAM_STALE_MAGIC;
debug(3, "write region header (0x%08x) @ 0x%08x", magic, addr);
CHECK_FLASH_OP(sdk_spi_flash_write(addr, &magic, 4));
return SYSPARAM_OK;
}
/** Initialize a context structure at the beginning of the active region */
static void _init_context(struct sysparam_context *ctx) {
memset(ctx, 0, sizeof(*ctx));
ctx->addr = _sysparam_info.cur_base;
}
/** Initialize a context structure at the end of the active region */
static sysparam_status_t init_write_context(struct sysparam_context *ctx) {
memset(ctx, 0, sizeof(*ctx));
ctx->addr = _sysparam_info.end_addr;
debug(3, "read entry header @ 0x%08x", ctx->addr);
CHECK_FLASH_OP(sdk_spi_flash_read(ctx->addr, &ctx->entry, ENTRY_HEADER_SIZE));
return SYSPARAM_OK;
}
/** Search through the region for an entry matching the specified id
*
* @param match_id The id to match, or 0 to match any key, or 0xff to scan
* to the end.
*/
static sysparam_status_t _find_entry(struct sysparam_context *ctx, uint8_t match_id) {
uint8_t prev_len;
while (ctx->addr + ENTRY_SIZE(ctx->entry.len) < _sysparam_info.end_addr) {
prev_len = ctx->entry.len;
ctx->addr += ENTRY_SIZE(ctx->entry.len);
debug(3, "read entry header @ 0x%08x", ctx->addr);
CHECK_FLASH_OP(sdk_spi_flash_read(ctx->addr, &ctx->entry, ENTRY_HEADER_SIZE));
if (ctx->entry.prev_len != prev_len) {
// Uh oh.. This should match the entry.len field from the
// previous entry. If it doesn't, it means that field may have
// been corrupted and we don't even know if we're in the right
// place anymore. We have to bail out.
debug(1, "prev_len mismatch at 0x%08x (%d != %d)", ctx->addr, ctx->entry.prev_len, prev_len);
ctx->addr = _sysparam_info.end_addr;
return SYSPARAM_ERR_CORRUPT;
}
if (ctx->entry.id) {
if (!(ctx->entry.id & 0x80)) {
// Key definition
ctx->max_key_id = ctx->entry.id;
ctx->unused_keys[ctx->entry.id >> 6] |= (1 << (ctx->entry.id & 0x3f));
if (!match_id) {
// We're looking for any key, so make this a matching key.
match_id = ctx->entry.id;
}
} else {
// Value entry
ctx->unused_keys[(ctx->entry.id >> 6) & 1] &= ~(1 << (ctx->entry.id & 0x3f));
}
if (ctx->entry.id == match_id) {
return SYSPARAM_OK;
}
} else {
// Deleted entry
ctx->compactable += ENTRY_SIZE(ctx->entry.len);
}
}
ctx->entry.len = 0;
ctx->entry.id = 0;
return SYSPARAM_NOTFOUND;
}
/** Read the payload from the current entry pointed to by `ctx` */
static inline sysparam_status_t _read_payload(struct sysparam_context *ctx, uint8_t *buffer, size_t buffer_size) {
debug(3, "read payload (%d) @ 0x%08x", min(buffer_size, ctx->entry.len), ctx->addr);
CHECK_FLASH_OP(sdk_spi_flash_read(ctx->addr + ENTRY_HEADER_SIZE, buffer, min(buffer_size, ctx->entry.len)));
//FIXME: check crc
return SYSPARAM_OK;
}
/** Find the entry corresponding to the specified key name */
static sysparam_status_t _find_key(struct sysparam_context *ctx, const char *key, uint8_t key_len, uint8_t *buffer) {
sysparam_status_t status;
while (true) {
// Find the next key entry
status = _find_entry(ctx, 0);
if (status != SYSPARAM_OK) return status;
if (!key) {
// We're looking for the next (any) key, so we're done.
break;
}
if (ctx->entry.len == key_len) {
status = _read_payload(ctx, buffer, key_len);
if (status < 0) return status;
if (!memcmp(key, buffer, key_len)) {
// We have a match
break;
}
}
}
return SYSPARAM_OK;
}
/** Write an entry at the specified address */
static inline sysparam_status_t _write_entry(uint32_t addr, uint8_t id, const uint8_t *payload, uint8_t len, uint8_t prev_len) {
struct entry_header entry;
debug(2, "Writing entry 0x%02x @ 0x%08x", id, addr);
entry.prev_len = prev_len;
entry.len = len;
entry.id = id;
entry.crc = 0; //FIXME: calculate crc
debug(3, "write entry header @ 0x%08x", addr);
CHECK_FLASH_OP(sdk_spi_flash_write(addr, &entry, ENTRY_HEADER_SIZE));
debug(3, "write payload (%d) @ 0x%08x", len, addr + ENTRY_HEADER_SIZE);
CHECK_FLASH_OP(sdk_spi_flash_write(addr + ENTRY_HEADER_SIZE, payload, len));
return SYSPARAM_OK;
}
/** Write the "tail" entry on the end of the region
* (this entry just contains the `prev_len` field with all others set to 0xff)
*/
static inline sysparam_status_t _write_entry_tail(uint32_t addr, uint8_t prev_len) {
struct entry_header entry;
entry.prev_len = prev_len;
entry.len = 0xff;
entry.id = 0xff;
entry.crc = 0xff;
debug(3, "write entry tail @ 0x%08x", addr);
CHECK_FLASH_OP(sdk_spi_flash_write(addr, &entry, ENTRY_HEADER_SIZE));
return SYSPARAM_OK;
}
/** Mark an entry as "deleted" so it won't be considered in future reads */
static inline sysparam_status_t _delete_entry(uint32_t addr) {
struct entry_header entry;
debug(2, "Deleting entry @ 0x%08x", addr);
debug(3, "read entry header @ 0x%08x", addr);
CHECK_FLASH_OP(sdk_spi_flash_read(addr, &entry, ENTRY_HEADER_SIZE));
// Set the ID to zero to mark it as "deleted"
entry.id = 0x00;
debug(3, "write entry header @ 0x%08x", addr);
CHECK_FLASH_OP(sdk_spi_flash_write(addr, &entry, ENTRY_HEADER_SIZE));
return SYSPARAM_OK;
}
/** Compact the current region, removing all deleted/unused entries, and write
* the result to the alternate region, then make the new alternate region the
* active one.
*
* @param key_id A pointer to the "current" key ID.
*
* NOTE: The value corresponding to the passed key ID will not be written to
* the output (because it is assumed it will be overwritten as the next step
* in `sysparam_set_data` anyway). When compacting, this routine will
* automatically update *key_id to contain the ID of this key in the new
* compacted result as well.
*/
static sysparam_status_t _compact_params(struct sysparam_context *ctx, uint8_t *key_id) {
uint32_t new_base = _sysparam_info.alt_base;
sysparam_status_t status;
uint32_t addr = new_base + REGION_HEADER_SIZE;
uint8_t current_key_id = 0;
sysparam_iter_t iter;
uint8_t prev_len = 0;
debug(1, "compacting region (current size %d, expect to recover %d%s bytes)...", _sysparam_info.end_addr - _sysparam_info.cur_base, ctx->compactable, (ctx->unused_keys[0] || ctx->unused_keys[1]) ? "+ (unused keys present)" : "");
status = _format_region(new_base);
if (status < 0) return status;
status = sysparam_iter_start(&iter);
if (status < 0) return status;
while (true) {
status = sysparam_iter_next(&iter);
if (status != SYSPARAM_OK) break;
current_key_id++;
// Write the key to the new region
debug(2, "writing %d key @ 0x%08x", current_key_id, addr);
status = _write_entry(addr, current_key_id, (uint8_t *)iter.key, iter.key_len, prev_len);
if (status < 0) break;
prev_len = iter.key_len;
addr += ENTRY_SIZE(iter.key_len);
if (iter.ctx->entry.id == *key_id) {
// Update key_id to have the correct id for the compacted result
*key_id = current_key_id;
// Don't copy the old value, since we'll just be deleting it
// and writing a new one as soon as we return.
continue;
}
// Copy the value to the new region
debug(2, "writing %d value @ 0x%08x", current_key_id, addr);
status = _write_entry(addr, current_key_id | 0x80, iter.value, iter.value_len, prev_len);
if (status < 0) break;
prev_len = iter.value_len;
addr += ENTRY_SIZE(iter.value_len);
}
sysparam_iter_end(&iter);
if (status >= 0) {
status = _write_entry_tail(addr, prev_len);
}
// If we broke out with an error, return the error instead of continuing.
if (status < 0) {
debug(1, "error encountered during compacting (%d)", status);
return status;
}
// Switch to officially using the new region.
status = _write_region_header(new_base, true);
if (status < 0) return status;
status = _write_region_header(_sysparam_info.cur_base, false);
if (status < 0) return status;
_sysparam_info.alt_base = _sysparam_info.cur_base;
_sysparam_info.cur_base = new_base;
_sysparam_info.end_addr = addr;
// Fix up ctx so it doesn't point to invalid stuff
memset(ctx, 0, sizeof(*ctx));
ctx->addr = addr;
ctx->entry.prev_len = prev_len;
ctx->max_key_id = current_key_id;
debug(1, "done compacting (current size %d)", _sysparam_info.end_addr - _sysparam_info.cur_base);
return SYSPARAM_OK;
}
/***************************** Public Functions ******************************/
sysparam_status_t sysparam_init(uint32_t base_addr) {
sysparam_status_t status;
uint32_t magic0, magic1;
struct sysparam_context ctx;
_sysparam_info.region_size = SYSPARAM_REGION_SECTORS * sdk_flashchip.sector_size;
// First, see if we can find an existing one.
debug(3, "read magic @ 0x%08x", base_addr);
CHECK_FLASH_OP(sdk_spi_flash_read(base_addr, &magic0, 4));
debug(3, "read magic @ 0x%08x", base_addr + _sysparam_info.region_size);
CHECK_FLASH_OP(sdk_spi_flash_read(base_addr + _sysparam_info.region_size, &magic1, 4));
if (magic0 == SYSPARAM_ACTIVE_MAGIC && magic1 == SYSPARAM_STALE_MAGIC) {
// Sysparam area found, first region is active
_sysparam_info.cur_base = base_addr;
_sysparam_info.alt_base = base_addr + _sysparam_info.region_size;
} else if (magic0 == SYSPARAM_STALE_MAGIC && magic1 == SYSPARAM_ACTIVE_MAGIC) {
// Sysparam area found, second region is active
_sysparam_info.cur_base = base_addr + _sysparam_info.region_size;
_sysparam_info.alt_base = base_addr;
} else if (magic0 == SYSPARAM_ACTIVE_MAGIC && magic1 == SYSPARAM_ACTIVE_MAGIC) {
// Both regions are marked as active. Not sure which to use.
// This can theoretically happen if something goes wrong at exactly the
// wrong time during compacting.
return SYSPARAM_ERR_CORRUPT;
} else if (magic0 == SYSPARAM_STALE_MAGIC && magic1 == SYSPARAM_STALE_MAGIC) {
// Both regions are marked as inactive. This shouldn't ever happen.
return SYSPARAM_ERR_CORRUPT;
} else {
// Looks like there's something else at that location entirely.
return SYSPARAM_NOTFOUND;
}
// Find the actual end
_sysparam_info.end_addr = _sysparam_info.cur_base + _sysparam_info.region_size;
_init_context(&ctx);
status = _find_entry(&ctx, 0xff);
if (status < 0) {
_sysparam_info.cur_base = 0;
_sysparam_info.alt_base = 0;
_sysparam_info.end_addr = 0;
return status;
}
if (status == SYSPARAM_OK) {
_sysparam_info.end_addr = ctx.addr;
}
return SYSPARAM_OK;
}
sysparam_status_t sysparam_create_area(uint32_t base_addr, bool force) {
sysparam_status_t status;
uint32_t buffer[SCAN_BUFFER_SIZE];
uint32_t addr;
int i;
size_t region_size = SYSPARAM_REGION_SECTORS * sdk_flashchip.sector_size;
if (!force) {
// First, scan through the area and make sure it's actually empty and
// we're not going to be clobbering something else important.
for (addr = base_addr; addr < base_addr + SYSPARAM_REGION_SECTORS * 2 * sdk_flashchip.sector_size; addr += SCAN_BUFFER_SIZE) {
debug(3, "read %d words @ 0x%08x", SCAN_BUFFER_SIZE, addr);
CHECK_FLASH_OP(sdk_spi_flash_read(addr, buffer, SCAN_BUFFER_SIZE * 4));
for (i = 0; i < SCAN_BUFFER_SIZE; i++) {
if (buffer[i] != 0xffffffff) {
// Uh oh, not empty.
return SYSPARAM_NOTFOUND;
}
}
}
}
if (_sysparam_info.cur_base == base_addr || _sysparam_info.alt_base == base_addr) {
// We're reformating the same region we're already using.
// De-initialize everything to force the caller to do a clean
// `sysparam_init()` afterwards.
memset(&_sysparam_info, 0, sizeof(_sysparam_info));
}
status = _format_region(base_addr);
if (status < 0) return status;
status = _format_region(base_addr + region_size);
if (status < 0) return status;
status = _write_entry_tail(base_addr + REGION_HEADER_SIZE, 0);
if (status < 0) return status;
status = _write_region_header(base_addr + region_size, false);
if (status < 0) return status;
status = _write_region_header(base_addr, true);
if (status < 0) return status;
return SYSPARAM_OK;
}
sysparam_status_t sysparam_get_data(const char *key, uint8_t **destptr, size_t *actual_length) {
struct sysparam_context ctx;
sysparam_status_t status;
size_t key_len = strlen(key);
uint8_t *buffer;
if (!_sysparam_info.cur_base) return SYSPARAM_ERR_NOINIT;
buffer = malloc(key_len + 2);
if (!buffer) return SYSPARAM_ERR_NOMEM;
do {
_init_context(&ctx);
status = _find_key(&ctx, key, key_len, buffer);
if (status != SYSPARAM_OK) break;
// Find the associated value
status = _find_entry(&ctx, ctx.entry.id | 0x80);
if (status != SYSPARAM_OK) break;
buffer = realloc(buffer, ctx.entry.len + 1);
if (!buffer) {
return SYSPARAM_ERR_NOMEM;
}
status = _read_payload(&ctx, buffer, ctx.entry.len);
if (status != SYSPARAM_OK) break;
// Zero-terminate the result, just in case (doesn't hurt anything for
// non-string data, and can avoid nasty mistakes if the caller wants to
// interpret the result as a string).
buffer[ctx.entry.len] = 0;
*destptr = buffer;
if (actual_length) *actual_length = ctx.entry.len;
return SYSPARAM_OK;
} while (false);
free(buffer);
if (actual_length) *actual_length = 0;
return status;
}
sysparam_status_t sysparam_get_data_static(const char *key, uint8_t *buffer, size_t buffer_size, size_t *actual_length) {
struct sysparam_context ctx;
sysparam_status_t status = SYSPARAM_OK;
size_t key_len = strlen(key);
if (!_sysparam_info.cur_base) return SYSPARAM_ERR_NOINIT;
// Supplied buffer must be at least as large as the key, or 2 bytes,
// whichever is larger.
if (buffer_size < max(key_len, 2)) return SYSPARAM_ERR_NOMEM;
if (actual_length) *actual_length = 0;
_init_context(&ctx);
status = _find_key(&ctx, key, key_len, buffer);
if (status != SYSPARAM_OK) return status;
status = _find_entry(&ctx, ctx.entry.id | 0x80);
if (status != SYSPARAM_OK) return status;
status = _read_payload(&ctx, buffer, buffer_size);
if (status != SYSPARAM_OK) return status;
if (actual_length) *actual_length = ctx.entry.len;
return SYSPARAM_OK;
}
sysparam_status_t sysparam_get_string(const char *key, char **destptr) {
// `sysparam_get_data` will zero-terminate the result as a matter of course,
// so no need to do that here.
return sysparam_get_data(key, (uint8_t **)destptr, NULL);
}
sysparam_status_t sysparam_get_int(const char *key, int32_t *result) {
char *buffer;
char *endptr;
int32_t value;
sysparam_status_t status;
status = sysparam_get_string(key, &buffer);
if (status != SYSPARAM_OK) return status;
value = strtol(buffer, &endptr, 0);
if (*endptr) {
// There was extra crap at the end of the string.
free(buffer);
return SYSPARAM_PARSEFAILED;
}
*result = value;
free(buffer);
return SYSPARAM_OK;
}
sysparam_status_t sysparam_get_bool(const char *key, bool *result) {
char *buffer;
int i;
sysparam_status_t status;
status = sysparam_get_string(key, &buffer);
if (status != SYSPARAM_OK) return status;
do {
for (i = 0; buffer[i]; i++) {
// Quick-and-dirty tolower(). Not perfect, but works for our
// purposes, and avoids needing to pull in additional libc stuff.
if (buffer[i] >= 0x41) buffer[i] |= 0x20;
}
if (!strcmp(buffer, "y") ||
!strcmp(buffer, "yes") ||
!strcmp(buffer, "t") ||
!strcmp(buffer, "true") ||
!strcmp(buffer, "1")) {
*result = true;
break;
}
if (!strcmp(buffer, "n") ||
!strcmp(buffer, "no") ||
!strcmp(buffer, "f") ||
!strcmp(buffer, "false") ||
!strcmp(buffer, "0")) {
*result = false;
break;
}
status = SYSPARAM_PARSEFAILED;
} while (0);
free(buffer);
return status;
}
sysparam_status_t sysparam_set_data(const char *key, const uint8_t *value, size_t value_len) {
struct sysparam_context ctx;
struct sysparam_context write_ctx;
sysparam_status_t status = SYSPARAM_OK;
uint8_t key_len = strlen(key);
uint8_t *buffer;
size_t free_space;
size_t needed_space;
bool free_value = false;
uint8_t key_id = 0;
uint32_t old_value_addr = 0;
if (!_sysparam_info.cur_base) return SYSPARAM_ERR_NOINIT;
if (!key_len) return SYSPARAM_ERR_BADVALUE;
if (value_len > 0xff) return SYSPARAM_ERR_BADVALUE;
if (!value) value_len = 0;
debug(1, "updating value for '%s' (%d bytes)", key, value_len);
if (value_len && ((intptr_t)value & 0x3)) {
// The passed value isn't word-aligned. This will be a problem later
// when calling `sdk_spi_flash_write`, so make a word-aligned copy.
buffer = malloc(value_len);
if (!buffer) return SYSPARAM_ERR_NOMEM;
memcpy(buffer, value, value_len);
value = buffer;
free_value = true;
}
// Create a working buffer for `_find_key` to use.
buffer = malloc(key_len);
if (!buffer) {
if (free_value) free((void *)value);
return SYSPARAM_ERR_NOMEM;
}
do {
_init_context(&ctx);
status = _find_key(&ctx, key, key_len, buffer);
if (status == SYSPARAM_OK) {
// Key already exists, see if there's a current value.
key_id = ctx.entry.id;
status = _find_entry(&ctx, key_id | 0x80);
if (status == SYSPARAM_OK) {
old_value_addr = ctx.addr;
}
}
if (status < 0) break;
if (value_len) {
if (old_value_addr) {
if (ctx.entry.len == value_len) {
// Are we trying to write the same value that's already there?
if (value_len > key_len) {
buffer = realloc(buffer, value_len);
if (!buffer) return SYSPARAM_ERR_NOMEM;
}
status = _read_payload(&ctx, buffer, value_len);
if (status == SYSPARAM_ERR_CORRUPT) {
// If the CRC check failed, don't worry about it. We're
// going to be deleting this entry anyway.
} else if (status < 0) {
break;
} else if (!memcmp(buffer, value, value_len)) {
// Yup, it's a match! No need to do anything further,
// just leave the current value as-is.
status = SYSPARAM_OK;
break;
}
}
// Since we will be deleting the old value (if any) make sure
// that the compactable count includes the space taken up by
// that entry too (even though it's not actually deleted yet)
ctx.compactable += ENTRY_SIZE(ctx.entry.len);
}
// Append new value to the end, but first make sure we have enough
// space.
free_space = _sysparam_info.cur_base + _sysparam_info.region_size - _sysparam_info.end_addr - 4;
needed_space = ENTRY_SIZE(value_len);
if (!key_id) {
// We did not find a previous key entry matching this key. We
// will need to add a key entry as well.
key_len = strlen(key);
needed_space += ENTRY_SIZE(key_len);
}
if (needed_space > free_space) {
// Can we compact things?
// First, scan all remaining entries up to the end so we can
// get a reasonably accurate "compactable" reading.
_find_entry(&ctx, 0xff);
if (needed_space <= free_space + ctx.compactable) {
// We should be able to get enough space by compacting.
status = _compact_params(&ctx, &key_id);
if (status < 0) break;
old_value_addr = 0;
} else if (ctx.unused_keys[0] || ctx.unused_keys[1]) {
// Compacting will gain more space than expected, because
// there are some keys that can be omitted too, but we
// don't know exactly how much that will gain, so all we
// can do is give it a try and see if it gives us enough.
status = _compact_params(&ctx, &key_id);
if (status < 0) break;
old_value_addr = 0;
}
free_space = _sysparam_info.cur_base + _sysparam_info.region_size - _sysparam_info.end_addr - 4;
}
if (needed_space > free_space) {
// Nothing we can do here.. We're full.
// (at least full enough that compacting won't help us store
// this value)
debug(1, "region full (need %d of %d remaining)", needed_space, free_space);
status = SYSPARAM_ERR_FULL;
break;
}
init_write_context(&write_ctx);
if (!key_id) {
// We need to write a key entry for a new key.
// If we didn't find the key, then we already know _find_entry
// has gone through the entire contents, and thus
// ctx.max_key_id has the largest key_id found in the whole
// region.
key_id = ctx.max_key_id + 1;
if (key_id > MAX_KEY_ID) {
if (ctx.unused_keys[0] || ctx.unused_keys[1]) {
status = _compact_params(&ctx, &key_id);
if (status < 0) break;
old_value_addr = 0;
} else {
debug(1, "out of ids!");
status = SYSPARAM_ERR_FULL;
break;
}
}
status = _write_entry(write_ctx.addr, key_id, (uint8_t *)key, key_len, write_ctx.entry.prev_len);
if (status < 0) break;
write_ctx.addr += ENTRY_SIZE(key_len);
write_ctx.entry.prev_len = key_len;
}
// Write new value
status = _write_entry(write_ctx.addr, key_id | 0x80, value, value_len, write_ctx.entry.prev_len);
if (status < 0) break;
write_ctx.addr += ENTRY_SIZE(value_len);
status = _write_entry_tail(write_ctx.addr, value_len);
if (status < 0) break;
_sysparam_info.end_addr = write_ctx.addr;
}
debug(1, "new addr is 0x%08x (%d bytes remaining)", _sysparam_info.end_addr, _sysparam_info.cur_base + _sysparam_info.region_size - _sysparam_info.end_addr - 4);
// Delete old value (if present) by setting it's id to 0x00
if (old_value_addr) {
status = _delete_entry(old_value_addr);
if (status < 0) break;
}
} while (false);
if (free_value) free((void *)value);
free(buffer);
return status;
}
sysparam_status_t sysparam_set_string(const char *key, const char *value) {
return sysparam_set_data(key, (const uint8_t *)value, strlen(value));
}
sysparam_status_t sysparam_set_int(const char *key, int32_t value) {
uint8_t buffer[12];
int len;
len = snprintf((char *)buffer, 12, "%d", value);
return sysparam_set_data(key, buffer, len);
}
sysparam_status_t sysparam_set_bool(const char *key, bool value) {
uint8_t buf[4] = {0xff, 0xff, 0xff, 0xff};
bool old_value;
// Don't write anything if the current setting already evaluates to the
// same thing.
if (sysparam_get_bool(key, &old_value) == SYSPARAM_OK) {
if (old_value == value) return SYSPARAM_OK;
}
buf[0] = value ? 'y' : 'n';
return sysparam_set_data(key, buf, 1);
}
sysparam_status_t sysparam_iter_start(sysparam_iter_t *iter) {
if (!_sysparam_info.cur_base) return SYSPARAM_ERR_NOINIT;
iter->bufsize = DEFAULT_ITER_BUF_SIZE;
iter->key = malloc(iter->bufsize);
if (!iter->key) {
iter->bufsize = 0;
return SYSPARAM_ERR_NOMEM;
}
iter->key_len = 0;
iter->value_len = 0;
iter->ctx = malloc(sizeof(struct sysparam_context));
if (!iter->ctx) {
free(iter->key);
iter->bufsize = 0;
return SYSPARAM_ERR_NOMEM;
}
_init_context(iter->ctx);
return SYSPARAM_OK;
}
sysparam_status_t sysparam_iter_next(sysparam_iter_t *iter) {
uint8_t buffer[2];
sysparam_status_t status;
size_t required_len;
struct sysparam_context *ctx = iter->ctx;
struct sysparam_context value_ctx;
size_t key_space;
while (true) {
status = _find_key(ctx, NULL, 0, buffer);
if (status != SYSPARAM_OK) return status;
memcpy(&value_ctx, ctx, sizeof(value_ctx));
status = _find_entry(&value_ctx, ctx->entry.id | 0x80);
if (status < 0) return status;
if (status == SYSPARAM_NOTFOUND) continue;
key_space = ROUND_TO_WORD_BOUNDARY(ctx->entry.len + 1);
required_len = key_space + value_ctx.entry.len + 1;
if (required_len > iter->bufsize) {
iter->key = realloc(iter->key, required_len);
if (!iter->key) {
iter->bufsize = 0;
return SYSPARAM_ERR_NOMEM;
}
iter->bufsize = required_len;
}
status = _read_payload(ctx, (uint8_t *)iter->key, iter->bufsize);
if (status < 0) return status;
// Null-terminate the key
iter->key[ctx->entry.len] = 0;
iter->key_len = ctx->entry.len;
iter->value = (uint8_t *)(iter->key + key_space);
status = _read_payload(&value_ctx, iter->value, iter->bufsize - key_space);
if (status < 0) return status;
// Null-terminate the value (just in case)
iter->value[value_ctx.entry.len] = 0;
iter->value_len = value_ctx.entry.len;
debug(2, "iter_next: (0x%08x) '%s' = (0x%08x) '%s' (%d)", ctx->addr, iter->key, value_ctx.addr, iter->value, iter->value_len);
return SYSPARAM_OK;
}
}
void sysparam_iter_end(sysparam_iter_t *iter) {
if (iter->key) free(iter->key);
if (iter->ctx) free(iter->ctx);
}