scrcpy/app/src/compat.c

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#include "compat.h"
#include "config.h"
#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#ifndef HAVE_STRDUP
char *strdup(const char *s) {
size_t size = strlen(s) + 1;
char *dup = malloc(size);
if (dup) {
memcpy(dup, s, size);
}
return dup;
}
#endif
#ifndef HAVE_ASPRINTF
int asprintf(char **strp, const char *fmt, ...) {
va_list va;
va_start(va, fmt);
int ret = vasprintf(strp, fmt, va);
va_end(va);
return ret;
}
#endif
#ifndef HAVE_VASPRINTF
int vasprintf(char **strp, const char *fmt, va_list ap) {
va_list va;
va_copy(va, ap);
int len = vsnprintf(NULL, 0, fmt, va);
va_end(va);
char *str = malloc(len + 1);
if (!str) {
return -1;
}
va_copy(va, ap);
int len2 = vsnprintf(str, len + 1, fmt, va);
(void) len2;
assert(len == len2);
va_end(va);
*strp = str;
return len;
}
#endif
#if !defined(HAVE_NRAND48) || !defined(HAVE_JRAND48)
#define SC_RAND48_MASK UINT64_C(0xFFFFFFFFFFFF) // 48 bits
#define SC_RAND48_A UINT64_C(0x5DEECE66D)
#define SC_RAND48_C 0xB
static inline uint64_t rand_iter48(uint64_t x) {
assert((x & ~SC_RAND48_MASK) == 0);
return (x * SC_RAND48_A + SC_RAND48_C) & SC_RAND48_MASK;
}
static uint64_t rand_iter48_xsubi(unsigned short xsubi[3]) {
uint64_t x = ((uint64_t) xsubi[0] << 32)
| ((uint64_t) xsubi[1] << 16)
| xsubi[2];
x = rand_iter48(x);
xsubi[0] = (x >> 32) & 0XFFFF;
xsubi[1] = (x >> 16) & 0XFFFF;
xsubi[2] = x & 0XFFFF;
return x;
}
#ifndef HAVE_NRAND48
long nrand48(unsigned short xsubi[3]) {
// range [0, 2^31)
return rand_iter48_xsubi(xsubi) >> 17;
}
#endif
#ifndef HAVE_JRAND48
long jrand48(unsigned short xsubi[3]) {
// range [-2^31, 2^31)
union {
uint32_t u;
int32_t i;
} v;
v.u = rand_iter48_xsubi(xsubi) >> 16;
return v.i;
}
#endif
#endif