Add hb-sort-r, a portable qsort_r() replacement
diff --git a/src/Makefile.sources b/src/Makefile.sources
index d162ebe..5787521 100644
--- a/src/Makefile.sources
+++ b/src/Makefile.sources
@@ -40,6 +40,7 @@
hb-shaper-impl-private.hh \
hb-shaper-private.hh \
hb-shaper.cc \
+ hb-sort-r.hh \
hb-string-array.hh \
hb-unicode-private.hh \
hb-unicode.cc \
diff --git a/src/hb-sort-r.hh b/src/hb-sort-r.hh
new file mode 100644
index 0000000..1b91b4d
--- /dev/null
+++ b/src/hb-sort-r.hh
@@ -0,0 +1,227 @@
+/* Isaac Turner 29 April 2014 Public Domain */
+#ifndef HB_SORT_R_HH
+#define HB_SORT_R_HH
+
+#include <hb-private.hh>
+
+/* From https://github.com/noporpoise/sort_r */
+/*
+
+hb_sort_r function to be exported.
+
+Parameters:
+ base is the array to be sorted
+ nel is the number of elements in the array
+ width is the size in bytes of each element of the array
+ compar is the comparison function
+ arg is a pointer to be passed to the comparison function
+
+void hb_sort_r(void *base, size_t nel, size_t width,
+ int (*compar)(const void *_a, const void *_b, void *_arg),
+ void *arg);
+
+*/
+
+#define _SORT_R_INLINE inline
+
+#if (defined __APPLE__ || defined __MACH__ || defined __DARWIN__ || \
+ defined __FreeBSD__ || defined __DragonFly__)
+# define _SORT_R_BSD
+#elif (defined _GNU_SOURCE || defined __gnu_hurd__ || defined __GNU__ || \
+ defined __linux__ || defined __MINGW32__ || defined __GLIBC__)
+# define _SORT_R_LINUX
+#elif (defined _WIN32 || defined _WIN64 || defined __WINDOWS__)
+# define _SORT_R_WINDOWS
+# undef _SORT_R_INLINE
+# define _SORT_R_INLINE __inline
+#else
+ /* Using our own recursive quicksort sort_r_simple() */
+#endif
+
+#if (defined NESTED_QSORT && NESTED_QSORT == 0)
+# undef NESTED_QSORT
+#endif
+
+/* swap a, b iff a>b */
+/* __restrict is same as restrict but better support on old machines */
+static _SORT_R_INLINE int sort_r_cmpswap(char *__restrict a, char *__restrict b, size_t w,
+ int (*compar)(const void *_a, const void *_b,
+ void *_arg),
+ void *arg)
+{
+ char tmp, *end = a+w;
+ if(compar(a, b, arg) > 0) {
+ for(; a < end; a++, b++) { tmp = *a; *a = *b; *b = tmp; }
+ return 1;
+ }
+ return 0;
+}
+
+/* Implement recursive quicksort ourselves */
+/* Note: quicksort is not stable, equivalent values may be swapped */
+static _SORT_R_INLINE void sort_r_simple(void *base, size_t nel, size_t w,
+ int (*compar)(const void *_a, const void *_b,
+ void *_arg),
+ void *arg)
+{
+ char *b = (char *)base, *end = b + nel*w;
+ if(nel < 7) {
+ /* Insertion sort for arbitrarily small inputs */
+ char *pi, *pj;
+ for(pi = b+w; pi < end; pi += w) {
+ for(pj = pi; pj > b && sort_r_cmpswap(pj-w,pj,w,compar,arg); pj -= w) {}
+ }
+ }
+ else
+ {
+ /* nel > 6; Quicksort */
+
+ /* Use median of first, middle and last items as pivot */
+ char *x, *y, *xend, ch;
+ char *pl, *pr;
+ char *last = b+w*(nel-1), *tmp;
+ char *l[3];
+ l[0] = b;
+ l[1] = b+w*(nel/2);
+ l[2] = last;
+
+ if(compar(l[0],l[1],arg) > 0) { tmp=l[0]; l[0]=l[1]; l[1]=tmp; }
+ if(compar(l[1],l[2],arg) > 0) {
+ tmp=l[1]; l[1]=l[2]; l[2]=tmp; /* swap(l[1],l[2]) */
+ if(compar(l[0],l[1],arg) > 0) { tmp=l[0]; l[0]=l[1]; l[1]=tmp; }
+ }
+
+ /* swap l[id], l[2] to put pivot as last element */
+ for(x = l[1], y = last, xend = x+w; x<xend; x++, y++) {
+ ch = *x; *x = *y; *y = ch;
+ }
+
+ pl = b;
+ pr = last;
+
+ while(pl < pr) {
+ for(; pl < pr; pl += w) {
+ if(sort_r_cmpswap(pl, pr, w, compar, arg)) {
+ pr -= w; /* pivot now at pl */
+ break;
+ }
+ }
+ for(; pl < pr; pr -= w) {
+ if(sort_r_cmpswap(pl, pr, w, compar, arg)) {
+ pl += w; /* pivot now at pr */
+ break;
+ }
+ }
+ }
+
+ sort_r_simple(b, (pl-b)/w, w, compar, arg);
+ sort_r_simple(pl+w, (end-(pl+w))/w, w, compar, arg);
+ }
+}
+
+
+#if defined NESTED_QSORT
+
+ static _SORT_R_INLINE void hb_sort_r(void *base, size_t nel, size_t width,
+ int (*compar)(const void *_a, const void *_b,
+ void *aarg),
+ void *arg)
+ {
+ int nested_cmp(const void *a, const void *b)
+ {
+ return compar(a, b, arg);
+ }
+
+ qsort(base, nel, width, nested_cmp);
+ }
+
+#else /* !NESTED_QSORT */
+
+ /* Declare structs and functions */
+
+ #if defined _SORT_R_BSD
+
+ /* Ensure qsort_r is defined */
+ extern void qsort_r(void *base, size_t nel, size_t width, void *thunk,
+ int (*compar)(void *_thunk, const void *_a, const void *_b));
+
+ #endif
+
+ #if defined _SORT_R_BSD || defined _SORT_R_WINDOWS
+
+ /* BSD (qsort_r), Windows (qsort_s) require argument swap */
+
+ struct sort_r_data
+ {
+ void *arg;
+ int (*compar)(const void *_a, const void *_b, void *_arg);
+ };
+
+ static _SORT_R_INLINE int sort_r_arg_swap(void *s, const void *a, const void *b)
+ {
+ struct sort_r_data *ss = (struct sort_r_data*)s;
+ return (ss->compar)(a, b, ss->arg);
+ }
+
+ #endif
+
+ #if defined _SORT_R_LINUX
+
+#if 0 /* BE: To avoid redeclaration warning. */
+ typedef int(* __compar_d_fn_t)(const void *, const void *, void *);
+ extern void qsort_r(void *base, size_t nel, size_t width,
+ __compar_d_fn_t __compar, void *arg)
+ __attribute__((nonnull (1, 4)));
+#endif
+
+ #endif
+
+ /* implementation */
+
+ static _SORT_R_INLINE void hb_sort_r(void *base, size_t nel, size_t width,
+ int (*compar)(const void *_a, const void *_b, void *_arg),
+ void *arg)
+ {
+ #if defined _SORT_R_LINUX
+
+ #if defined __GLIBC__ && ((__GLIBC__ < 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ < 8))
+
+ /* no qsort_r in glibc before 2.8, need to use nested qsort */
+ sort_r_simple(base, nel, width, compar, arg);
+
+ #else
+
+ qsort_r(base, nel, width, compar, arg);
+
+ #endif
+
+ #elif defined _SORT_R_BSD
+
+ struct sort_r_data tmp;
+ tmp.arg = arg;
+ tmp.compar = compar;
+ qsort_r(base, nel, width, &tmp, sort_r_arg_swap);
+
+ #elif defined _SORT_R_WINDOWS
+
+ struct sort_r_data tmp;
+ tmp.arg = arg;
+ tmp.compar = compar;
+ qsort_s(base, nel, width, sort_r_arg_swap, &tmp);
+
+ #else
+
+ /* Fall back to our own quicksort implementation */
+ sort_r_simple(base, nel, width, compar, arg);
+
+ #endif
+ }
+
+#endif /* !NESTED_QSORT */
+
+#undef _SORT_R_INLINE
+#undef _SORT_R_WINDOWS
+#undef _SORT_R_LINUX
+#undef _SORT_R_BSD
+
+#endif /* HB_SORT_R_HH */
