@@ -172,7 +172,7 @@ libs: $(LIBRARY_A) $(LIBRARY_SO)
VALGRIND = $(shell which valgrind)
UTEST_DIR = utest
-UTEST_BINARY = trace-utest
+UTEST_BINARY = eval-utest
test: force $(LIBRARY_STATIC)
ifneq ($(CUNIT_INSTALLED),1)
@@ -127,4 +127,11 @@ struct traceeval_iterator;
struct traceeval;
+/* Histogram interfaces */
+
+struct traceeval *traceeval_init(const struct traceeval_type *keys,
+ const struct traceeval_type *vals);
+
+void traceeval_release(struct traceeval *teval);
+
#endif /* __LIBTRACEEVAL_HIST_H__ */
@@ -4,6 +4,7 @@ include $(src)/scripts/utils.mk
OBJS =
OBJS += trace-analysis.o
+OBJS += histograms.o
OBJS := $(OBJS:%.o=$(bdir)/%.o)
new file mode 100644
@@ -0,0 +1,310 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * libtraceeval histogram interface implementation.
+ *
+ * Copyright (C) 2023 Google Inc, Stevie Alvarez <stevie.6strings@gmail.com>
+ */
+
+#include <stdbool.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdio.h>
+
+#include <traceeval-hist.h>
+
+/* A key-value pair */
+struct entry {
+ union traceeval_data *keys;
+ union traceeval_data *vals;
+};
+
+/* A table of key-value entries */
+struct hist_table {
+ struct entry *map;
+ size_t nr_entries;
+};
+
+/* Histogram */
+struct traceeval {
+ struct traceeval_type *key_types;
+ struct traceeval_type *val_types;
+ struct hist_table *hist;
+ size_t nr_key_types;
+ size_t nr_val_types;
+};
+
+/*
+ * print_err() - print an error message
+ * @fmt: String format
+ * @...: (optional) Additional arguments to print in conjunction with @format
+ */
+static void print_err(const char *fmt, ...)
+{
+ va_list ap;
+
+ va_start(ap, fmt);
+ vfprintf(stderr, fmt, ap);
+ va_end(ap);
+ fprintf(stderr, "\n");
+}
+
+/*
+ * type_release() - free a struct traceeval_type array
+ * @defs: The array to release
+ * @len: The length of @defs
+ *
+ * It is assumed that all elements of @defs, within the length of @len, have
+ * name fields initialized to valid pointers.
+ *
+ * This function was designed to be used on an array allocated by type_alloc().
+ * Note that type_alloc() initializes all name fields of elements within the
+ * returned size.
+ */
+static void type_release(struct traceeval_type *defs, size_t len)
+{
+ if (!defs)
+ return;
+
+ for (size_t i = 0; i < len; i++) {
+ free(defs[i].name);
+ }
+
+ free(defs);
+}
+
+/*
+ * type_alloc() - clone a struct traceeval_type array
+ * @defs: The original array
+ * @copy: A pointer to where to place the @defs copy
+ *
+ * Clone traceeval_type array @defs to the heap, and place in @copy.
+ * @defs must be terminated with an instance of type TRACEEVAL_TYPE_NONE.
+ *
+ * The size of the copy pointed to by @copy is returned. It counts all elements
+ * in @defs excluding the terminating TRACEEVAL_TYPE_NONE traceeval_type.
+ * The copy contains everything from @defs excluding the TRACEEVAL_TYPE_NONE
+ * traceeval_type.
+ * On error, copy is set to point to NULL.
+ *
+ * The name field of each element of @defs (except for the terminating
+ * TRACEEVAL_TYPE_NONE) must be a NULL-terminated string. The validity of the
+ * name field is not checked, but errors are returned upon finding unset name
+ * fields and string duplication failures. It is guaranteed that all elements
+ * of the copy within the returned size have valid pointers in their name
+ * fields.
+ *
+ * Returns the size of the array pointed to by @copy, or -1 on error.
+ */
+static size_t type_alloc(const struct traceeval_type *defs,
+ struct traceeval_type **copy)
+{
+ struct traceeval_type *new_defs = NULL;
+ size_t size;
+ size_t i;
+
+ if (!defs) {
+ *copy = NULL;
+ return 0;
+ }
+
+ for (size = 0; defs && defs[size].type != TRACEEVAL_TYPE_NONE; size++)
+ ;
+
+ if (size) {
+ new_defs = calloc(size, sizeof(*new_defs));
+ } else {
+ *copy = NULL;
+ return 0;
+ }
+
+ for (i = 0; i < size; i++) {
+ /* copy current def data to new_def */
+ new_defs[i] = defs[i];
+
+ /* copy name to heap, ensures name copied */
+ if (!defs[i].name)
+ goto fail;
+ new_defs[i].name = strdup(defs[i].name);
+
+ if (!new_defs[i].name)
+ goto fail;
+ }
+
+ *copy = new_defs;
+ return size;
+
+fail:
+ if (defs[i].name)
+ print_err("Failed to allocate traceeval_type %zu", size);
+ else
+ print_err("traceeval_type list missing a name");
+
+ for (; i >=0; i--)
+ free(new_defs[i].name);
+ free(new_defs);
+ *copy = NULL;
+ return -1;
+}
+
+/*
+ * traceeval_init - create a traceeval descriptor
+ * @keys: Defines the keys to differentiate traceeval entries
+ * @vals: Defines values attached to entries differentiated by @keys.
+ *
+ * The @keys and @vals define how the traceeval instance will be populated.
+ * The @keys will be used by traceeval_query() to find an instance within
+ * the "histogram". Note, both the @keys and @vals array must end with:
+ * { .type = TRACEEVAL_TYPE_NONE }.
+ *
+ * The @keys and @vals passed in are copied for internal use.
+ *
+ * For any member of @keys or @vals that isn't of type TRACEEVAL_TYPE_NONE,
+ * the name field must be a null-terminated string. Members of type
+ * TRACEEVAL_TYPE_NONE are used to terminate the array, therefore their other
+ * fields are ignored.
+ *
+ * @vals can be NULL or start with its type field as TRACEEVAL_TYPE_NONE to
+ * define the values of the histogram to be empty.
+ * @keys must be populated with at least one element that is not of type
+ * TRACEEVAL_TYPE_NONE.
+ *
+ * Returns the descriptor on success, or NULL on error.
+ */
+struct traceeval *traceeval_init(const struct traceeval_type *keys,
+ const struct traceeval_type *vals)
+{
+ struct traceeval *teval;
+ char *err_msg;
+
+ if (!keys)
+ return NULL;
+
+ if (keys->type == TRACEEVAL_TYPE_NONE) {
+ err_msg = "Keys cannot start with type TRACEEVAL_TYPE_NONE";
+ goto fail;
+ }
+
+ /* alloc teval */
+ teval = calloc(1, sizeof(*teval));
+ if (!teval) {
+ err_msg = "Failed to allocate memory for traceeval instance";
+ goto fail;
+ }
+
+ /* alloc key types */
+ teval->nr_key_types = type_alloc(keys, &teval->key_types);
+ if (teval->nr_key_types <= 0) {
+ err_msg = "Failed to allocate user defined keys";
+ goto fail_release;
+ }
+
+ /* alloc val types */
+ teval->nr_val_types = type_alloc(vals, &teval->val_types);
+ if (teval->nr_val_types < 0) {
+ err_msg = "Failed to allocate user defined values";
+ goto fail_release;
+ }
+
+ /* alloc hist */
+ teval->hist = calloc(1, sizeof(*teval->hist));
+ if (!teval->hist) {
+ err_msg = "Failed to allocate memory for histogram";
+ goto fail_release;
+ }
+
+ return teval;
+
+fail_release:
+ traceeval_release(teval);
+
+fail:
+ print_err(err_msg);
+ return NULL;
+}
+
+/*
+ * Free any specified dynamic data in @data.
+ */
+static void clean_data(union traceeval_data *data, struct traceeval_type *defs,
+ size_t size)
+{
+ size_t i;
+
+ if (!data || !defs) {
+ if (data)
+ print_err("Data to be freed without accompanied types!");
+ return;
+ }
+
+ for (i = 0; i < size; i++) {
+ switch (defs[i].type) {
+ case TRACEEVAL_TYPE_STRING:
+ free(data[i].string);
+ break;
+ case TRACEEVAL_TYPE_DYNAMIC:
+ if (defs[i].dyn_release)
+ defs[i].dyn_release(defs + i, data[i].dyn_data);
+ break;
+ default:
+ break;
+ }
+ }
+}
+
+/*
+ * Free all possible data stored within the entry.
+ */
+static void clean_entry(struct entry *entry, struct traceeval *teval)
+{
+ if (!entry)
+ return;
+
+ /* free dynamic traceeval_data */
+ clean_data(entry->keys, teval->key_types, teval->nr_key_types);
+ clean_data(entry->vals, teval->val_types, teval->nr_val_types);
+ free(entry->keys);
+ free(entry->vals);
+}
+
+/*
+ * Free the hist_table allocated to a traceeval instance.
+ */
+static void hist_table_release(struct traceeval *teval)
+{
+ struct hist_table *hist = teval->hist;
+
+ if (!hist)
+ return;
+
+ for (size_t i = 0; i < hist->nr_entries; i++) {
+ clean_entry(hist->map + i, teval);
+ }
+
+ free(hist->map);
+ free(hist);
+ teval->hist = NULL;
+}
+
+/*
+ * traceeval_release - release a traceeval descriptor
+ * @teval: An instance of traceeval returned by traceeval_init()
+ *
+ * When the caller of traceeval_init() is done with the returned @teval,
+ * it must call traceeval_release().
+ *
+ * This frees all internally allocated data of @teval and will call the
+ * corresponding dyn_release() functions registered for keys and values of
+ * type TRACEEVAL_TYPE_DYNAMIC.
+ */
+void traceeval_release(struct traceeval *teval)
+{
+ if (!teval)
+ return;
+
+ hist_table_release(teval);
+ type_release(teval->key_types, teval->nr_key_types);
+ type_release(teval->val_types, teval->nr_val_types);
+ teval->key_types = NULL;
+ teval->val_types = NULL;
+ free(teval);
+}