commit fc1e680d3cc648ccda11b8cce3c5c6f833f9fc63
parent 8b6bc0fc0643d51c3092c8aaf10718574136cfc5
Author: Yersa Nordman <yersa@finwo.nl>
Date: Sun, 1 Oct 2023 23:04:24 +0200
Merge branch 'optimization'
Diffstat:
4 files changed, 146 insertions(+), 118 deletions(-)
diff --git a/benchmark.c b/benchmark.c
@@ -8,29 +8,47 @@
#include <unistd.h>
#include "finwo/benchmark.h"
+#include "mindex.h"
-/* usleep(): Sleep for the requested number of microseconds. */
-int musleep(long usec) {
- struct timespec ts;
- int res;
+static void fn_purge(const void *item, void *udata) {
+ free(item);
+ // Intentionally empty
+}
- if (usec < 0) {
- return -1;
- }
+static int fn_compare_string(const void *a, const void *b, void *udata) {
+ const char *sa = (char*)a;
+ const char *sb = (char*)b;
+ return strcmp(sa, sb);
+}
- ts.tv_sec = usec / 1000000;
- ts.tv_nsec = (usec % 1000000) * 1000;
+char random_char() {
+ char *alphabet = "0123456789abcdef";
+ int length = strlen(alphabet);
+ return alphabet[rand() % length];
+}
- do {
- res = nanosleep(&ts, &ts);
- } while (res && errno == EINTR);
+char *random_str(int length) {
+ char *str = malloc(length + 1);
+ for(int i=0; i<length; i++) {
+ str[i] = random_char();
+ }
+ str[length] = '\0';
+ return str;
+}
- return res;
+void mindex_bmark_rstr_1024() {
+ for(int i=0; i<1024; i++) {
+ free(random_str(16));
+ }
}
-void mindex_some_bmark_method() {
- // Intentionally empty
- musleep(100);
+void mindex_bmark_assign_1024() {
+ struct mindex_t *mindex = mindex_init(fn_compare_string, fn_purge, NULL);
+ for(int i=0; i<1024; i++) {
+ mindex_set(mindex, random_str(16));
+ }
+
+ mindex_free(mindex);
}
int main() {
@@ -39,6 +57,8 @@ int main() {
1, 5, 50, 95, 99, 0
};
- BMARK(mindex_some_bmark_method);
+ BMARK(mindex_bmark_rstr_1024);
+ BMARK(mindex_bmark_assign_1024);
return bmark_run(100, percentiles);
+ return 0;
}
diff --git a/package.ini b/package.ini
@@ -1,7 +1,6 @@
[dependencies]
finwo/assert=https://github.com/finwo/c-assert/archive/refs/tags/edge.tar.gz
finwo/benchmark=https://github.com/finwo/c-benchmark/archive/refs/tags/edge.tar.gz
-noporpoise/sort_r=https://raw.githubusercontent.com/finwo/dep-repository/main/noporpoise/sort_r/package.ini
[export]
config.mk=config.mk
include/finwo/mindex.h=src/mindex.h
diff --git a/src/mindex.c b/src/mindex.c
@@ -3,14 +3,23 @@
#include <stdlib.h>
#include <string.h>
-#include "noporpoise/sort_r.h"
-
#include "mindex.h"
#ifndef MINDEX_SPARE
#define MINDEX_SPARE 16
#endif
+int mindex_signal_found = 1;
+int mindex_signal_over = 2;
+int mindex_signal_under = 4;
+int mindex_signal_empty = 8;
+
+struct mindex_find_response {
+ int signal;
+ int index;
+ void *value; // NULL = not found
+};
+
struct mindex_t * mindex_init(int (*compare)(const void *a, const void *b, void *udata), void (*purge)(const void *item, void *udata), void *udata) {
struct mindex_t *mindex = malloc(sizeof(struct mindex_t));
mindex->compare = compare;
@@ -18,113 +27,119 @@ struct mindex_t * mindex_init(int (*compare)(const void *a, const void *b, void
mindex->udata = udata;
mindex->items = malloc(MINDEX_SPARE * sizeof(void*));
mindex->length = 0;
- mindex->spare = MINDEX_SPARE;
+ mindex->max = MINDEX_SPARE;
return mindex;
}
-static int mindex_compare_wrap(const void *a, const void *b, void *udata) {
- struct mindex_t *mindex = udata;
- return mindex->compare(
- *(void**)a,
- *(void**)b,
- mindex->udata
- );
-}
+struct mindex_find_response * mindex_find(const struct mindex_t *mindex, const void *pattern, void **items, int length) {
+ int acc, idx, newlength;
+ struct mindex_find_response *resp;
+
+ // Nothing to search = done
+ if (length <= 0) {
+ return &((struct mindex_find_response){
+ .signal = mindex_signal_empty,
+ .index = 0,
+ .value = NULL,
+ });
+ }
-void mindex_set(struct mindex_t *mindex, void *item) {
+ // Make the actual comparison, splitting the array in 2
+ idx = length / 2;
+ acc = mindex->compare(pattern, items[idx], mindex->udata);
- // Check if the item is already in the list
- void *found = mindex_get(mindex, item);
+ // Pattern = below middlepoint
+ if (acc < 0) {
- // The exact pointer already there = done
- if (found && (item == found)) {
- return;
- }
+ // Limit deeper search to only the left side
+ newlength = idx;
- // Different pointer, so remove from the list
- // Indicate to lib user that it needs to be purged from mem
- if (found) {
- mindex_delete(mindex, item);
- }
+ // Nothing to our left, item not found
+ if (newlength <= 0) {
+ return &((struct mindex_find_response){
+ .signal = mindex_signal_under,
+ .index = 0,
+ .value = NULL,
+ });
+ }
+
+ // Limit deeper search to only the left side
+ newlength = idx;
+
+ // Run the find on items below
+ resp = mindex_find(mindex, pattern, items, newlength);
- // Allocate more space if we ran out
- if (!mindex->spare) {
- mindex->items = realloc(mindex->items, (mindex->length + MINDEX_SPARE) * sizeof(void*));
- mindex->spare = MINDEX_SPARE;
+ // Surpress "over" signal
+ resp->signal &= ~mindex_signal_over;
+
+ return resp;
}
- // Add the new item to the end of the list
- mindex->items[mindex->length] = item;
- mindex->length++;
- mindex->spare--;
+ // Pattern = above middlepoint
+ if (acc > 0) {
- // Sort the list
- sort_r(mindex->items, mindex->length, sizeof(void *), mindex_compare_wrap, mindex);
+ // Calculate new index to check
+ newlength = length - 1 - idx;
- // Done
-}
+ // Nothing to our right, item not found
+ if (newlength <= 0) {
+ return &((struct mindex_find_response){
+ .signal = mindex_signal_over,
+ .index = length,
+ .value = NULL,
+ });
+ }
+
+ // Get stats on the right-side of our pivot & translate response index
+ resp = mindex_find(mindex, pattern, &(items[idx+1]), newlength);
+ resp->index += idx + 1;
-// Returns the INDEX within the items, not the item itself
-int mindex_get_internal(void **items, size_t length, void *pattern, int (*compare)(const void *a, const void *b, void *udata), void *udata) {
- int sub;
+ // Surpress "under" signal
+ resp->signal &= ~mindex_signal_under;
- // No entries = not found
- if (length < 1) {
- return -1;
+ return resp;
}
- // Test the middle of the array
- size_t testIdx = length / 2;
- int compare_result = compare(items[testIdx], pattern, udata);
+ // Found = win
+ return &((struct mindex_find_response){
+ .signal = mindex_signal_found,
+ .index = idx,
+ .value = items[idx],
+ });
+}
+
+void mindex_set(struct mindex_t *mindex, void *item) {
+ size_t movesize;
- // Match = found
- if (compare_result == 0) {
- return testIdx;
+ // Ensure we have space to insert a new item
+ if (mindex->max == mindex->length) {
+ mindex->max = mindex->max * 2;
+ mindex->items = realloc(mindex->items, mindex->max * sizeof(void*));
}
- // Pattern = to the right
- if (compare_result < 0) {
- sub = mindex_get_internal(
- &(items[testIdx+1]),
- length - testIdx - 1,
- pattern,
- compare,
- udata
- );
-
- // Pass along error code
- if (sub < 0) {
- return sub;
- }
+ // Find the index to insert (or already-occupied pattern)
+ struct mindex_find_response *resp = mindex_find(mindex, item, mindex->items, mindex->length);
- // Return mapped location
- return sub + testIdx + 1;
+ // Item already in there, notify we skipped insertion
+ if (resp->signal & mindex_signal_found) {
+ mindex->items[resp->index] = item;
+ mindex->purge(item, mindex->udata);
+ return;
}
- // Pattern to the left
- if (compare_result > 0) {
- return mindex_get_internal(
- items,
- testIdx,
- pattern,
- compare,
- udata
- );
- }
+ // Move items above aside for the insertion
+ // Essentially single-step insertion sort
+ movesize = (mindex->length - resp->index) * sizeof(void*);
+ memmove(&(mindex->items[resp->index + 1]), &(mindex->items[resp->index]), movesize);
+ mindex->items[resp->index] = item;
+ mindex->length++;
- // Should never be called
- return -2;
+ // Aanndd.. We're done
}
void * mindex_get(struct mindex_t *mindex, void *pattern) {
- int idx = mindex_get_internal(mindex->items, mindex->length, pattern, mindex->compare, mindex->udata);
-
- // Not found
- if (idx < 0) {
- return NULL;
- }
-
- return mindex->items[idx];
+ struct mindex_find_response *resp = mindex_find(mindex, pattern, mindex->items, mindex->length);
+ return resp->value;
}
void * mindex_rand(struct mindex_t *mindex) {
@@ -134,33 +149,27 @@ void * mindex_rand(struct mindex_t *mindex) {
return mindex->items[rand() % mindex->length];
}
-// TODO: mindex_delete_internal(..., items, idx)
-// TODO: delete an exact pointer, not a pattern (extra fn?)
-
void mindex_delete(struct mindex_t *mindex, void *pattern) {
- int idx = mindex_get_internal(mindex->items, mindex->length, pattern, mindex->compare, mindex->udata);
- if (idx < 0) {
+ struct mindex_find_response *resp = mindex_find(mindex, pattern, mindex->items, mindex->length);
+
+ // Not found = done
+ if (!(resp->signal & mindex_signal_found)) {
return;
}
// Call user's purge method
- void *item = mindex->items[idx];
+ void *item = mindex->items[resp->index];
mindex->purge(item, mindex->udata);
// Move everything on it's right to it
- void *dst = &(mindex->items[idx]);
- void *src = &(mindex->items[idx+1]);
- memmove(dst, src, (mindex->length - idx - 1) * sizeof(void*));
+ void *dst = &(mindex->items[resp->index]);
+ void *src = &(mindex->items[resp->index+1]);
+ memmove(dst, src, (mindex->length - resp->index - 1) * sizeof(void*));
- // Update our size trackers
+ // Update our size tracker
mindex->length--;
- mindex->spare++;
- // Free some memory if we have a lot of spares
- if (mindex->spare > (MINDEX_SPARE*2)) {
- mindex->items = realloc(mindex->items, (mindex->length + MINDEX_SPARE) * sizeof(void*));
- mindex->spare = MINDEX_SPARE;
- }
+ // TODO: reduce memory usage?
// Done
}
diff --git a/src/mindex.h b/src/mindex.h
@@ -8,7 +8,7 @@ struct mindex_t {
void (*purge)(const void *item, void *udata);
void *udata;
size_t length;
- size_t spare;
+ size_t max;
void **items;
};
