Large commit:

- Moved stc/algo/cspan.h to stc/cspan.h - its a data view type similar to csview. +Many updates. Added docs/cspan_api.md page!
- Update c11/fmt.h to VER 2.0: NEW API, see test. NOTE: fmt.h is not officially part of STC, as it is C11, and STC is C99.
- Renamed crange_LITERAL() back to crange_literal(), and cspan_LITERAL() to cspan_literal(). These returns a compound literal (lvalue) that can be passed to a c_FOR*-iterator.

1 files changed, 154 insertions, 0 deletions

diff --git a/include/stc/cspan.h b/include/stc/cspan.h
new file mode 100644
index 00000000..f5114a11
--- /dev/null
+++ b/include/stc/cspan.h
@@ -0,0 +1,154 @@
+/* MIT License
+ *
+ * Copyright (c) 2023 Tyge Løvset
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+/*
+#include <stdio.h>
+#include <stc/cspan.h>
+#include <stc/algo/filter.h>
+using_cspan(Span2f, float, 2);
+using_cspan(Intspan, int, 1);
+
+int demo1() {
+    float raw[4*5];
+    Span2f ms = cspan_make(raw, 4, 5);
+    
+    for (size_t i=0; i<ms.dim[0]; i++)
+        for (size_t j=0; j<ms.dim[1]; j++)
+            *cspan_at(&ms, i, j) = i*1000 + j;
+
+    printf("%f\n", *cspan_at(&span, 3, 4));
+}
+
+int demo2() {
+    int array[] = {1, 2, 3, 4, 5};
+    Intspan span = cspan_from(array);
+    
+    c_FOREACH (i, Intspan, span)
+        printf(" %d", *i.ref);
+    puts("");
+    
+    // use a temporary Intspan object.
+    c_FORFILTER (i, Intspan, cspan_literal(Intspan, {10, 20, 30, 23, 22, 21})
+                  , c_FLT_SKIPWHILE(i, *i.ref < 25)
+                 && (*i.ref & 1) == 0 // even only
+                  , c_FLT_TAKE(i, 2)) // break after 2
+        printf(" %d", *i.ref);
+    puts("");
+}
+*/
+#ifndef STC_CSPAN_H_INCLUDED
+#define STC_CSPAN_H_INCLUDED
+
+#include "ccommon.h"
+
+#define using_cspan(Self, T, RANK) \
+    typedef T Self##_value, Self##_raw; \
+    typedef struct { Self##_value *ref, *end; } Self##_iter; \
+    typedef struct { Self##_value *data; uint32_t dim[RANK]; } Self; \
+    \
+    STC_INLINE Self##_iter Self##_begin(const Self* self) { \
+        Self##_iter it = {self->data, self->data + cspan_size(self)}; \
+        return it; \
+    } \
+    STC_INLINE Self##_iter Self##_end(const Self* self) { \
+        Self##_iter it = {NULL, self->data + cspan_size(self)}; \
+        return it; \
+    } \
+    STC_INLINE void Self##_next(Self##_iter* it) \
+        { if (++it->ref == it->end) it->ref = NULL; } \
+    struct stc_nostruct
+
+#define using_cspan2(Self, T) using_cspan(Self##1, T, 1); using_cspan(Self##2, T, 2)
+#define using_cspan3(Self, T) using_cspan2(Self, T); using_cspan(Self##3, T, 3)
+#define using_cspan4(Self, T) using_cspan3(Self, T); using_cspan(Self##4, T, 4)
+
+#define cspan_check_rank(self, rank) c_STATIC_ASSERT(cspan_rank(self) == rank)
+
+#define cspan_literal(S, ...) \
+    ((S){.data = (S##_value[])__VA_ARGS__, \
+         .dim = {sizeof((S##_value[])__VA_ARGS__)/sizeof(S##_value)}})
+
+#define cspan_make(data, ...) \
+    {data, {__VA_ARGS__}}
+
+/* create a cspan from a cvec, cstack, cdeq, cqueue, or cpque (heap) */
+#define cspan_from(container) \
+    {(container)->data, {(container)->_len}}
+
+#define cspan_from_array(array) \
+    {(array) + c_STATIC_ASSERT(sizeof(array) != sizeof(void*)), {c_ARRAYLEN(array)}}
+
+#define cspan_size(self) _cspan_size((self)->dim, cspan_rank(self))
+#define cspan_rank(self) c_ARRAYLEN((self)->dim)
+#define cspan_index(self, ...) \
+    c_PASTE(_cspan_i, c_NUMARGS(__VA_ARGS__))((self)->dim, __VA_ARGS__) + \
+    cspan_check_rank(self, c_NUMARGS(__VA_ARGS__))
+
+#define cspan_reshape(self, ...) \
+    (void)memcpy((self)->dim, (uint32_t[]){__VA_ARGS__}, \
+                 sizeof((self)->dim) + cspan_check_rank(self, c_NUMARGS(__VA_ARGS__)))
+
+#define cspan_at(self, ...) ((self)->data + cspan_index(self, __VA_ARGS__))
+
+#define cspan_slice4(self, x0, width) \
+    {cspan_at(self, x0, 0, 0, 0), {width, (self)->dim[1], (self)->dim[2], (self)->dim[3]}}
+#define cspan_slice3(self, x0, width) \
+    {cspan_at(self, x0, 0, 0), {width, (self)->dim[1], (self)->dim[2]}}
+#define cspan_slice2(self, x0, width) \
+    {cspan_at(self, x0, 0), {width, (self)->dim[1]}}
+#define cspan_slice1(self, x0, width) \
+    {cspan_at(self, x0), {width}}
+
+#define cspan_4to3(self, x) \
+    {cspan_at(self, x, 0, 0, 0), {(self)->dim[1], (self)->dim[2], (self)->dim[3]}}
+#define cspan_4to2(self, x, y) \
+    {cspan_at(self, x, y, 0, 0), {(self)->dim[2], (self)->dim[3]}}
+#define cspan_4to1(self, x, y, z) \
+    {cspan_at(self, x, y, z, 0), {(self)->dim[3]}}
+#define cspan_3to2(self, x) \
+    {cspan_at(self, x, 0, 0), {(self)->dim[1], (self)->dim[2]}}
+#define cspan_3to1(self, x, y) \
+    {cspan_at(self, x, y, 0), {(self)->dim[2]}}
+#define cspan_2to1(self, x) \
+    {cspan_at(self, x, 0), {(self)->dim[1]}}
+
+STC_INLINE size_t _cspan_i1(const uint32_t dim[1], uint32_t x)
+    { c_ASSERT(x < dim[0]); return x; }
+
+STC_INLINE size_t _cspan_i2(const uint32_t dim[2], uint32_t x, uint32_t y)
+    { c_ASSERT(x < dim[0] && y < dim[1]); return dim[1]*x + y; }
+
+STC_INLINE size_t _cspan_i3(const uint32_t dim[3], uint32_t x, uint32_t y, uint32_t z) {
+    c_ASSERT(x < dim[0] && y < dim[1] && z < dim[2]);
+    return dim[2]*(dim[1]*x + y) + z;
+}
+STC_INLINE size_t _cspan_i4(const uint32_t dim[4], uint32_t x, uint32_t y, uint32_t z, uint32_t w) {
+    c_ASSERT(x < dim[0] && y < dim[1] && z < dim[3] && w < dim[3]);
+    return dim[3]*(dim[2]*(dim[1]*x + y) + z) + w;
+}
+STC_INLINE size_t _cspan_size(const uint32_t dim[], unsigned rank) {
+    size_t sz = dim[0];
+    while (rank --> 1) sz *= dim[rank];
+    return sz;
+}
+
+#endif