1 /* 2 * lib_strbuf.c - init_lib() and library string storage 3 */ 4 #ifdef HAVE_CONFIG_H 5 #include <config.h> 6 #endif 7 8 #include <isc/mutex.h> 9 #include <isc/net.h> 10 #include <isc/result.h> 11 12 #include "ntp_fp.h" 13 #include "ntp_stdlib.h" 14 #include "lib_strbuf.h" 15 16 #define LIB_NUMBUF 10 17 18 /* 19 * Storage declarations 20 */ 21 static char lib_stringbuf_storage[LIB_NUMBUF][LIB_BUFLENGTH]; 22 static char * lib_stringbuf[LIB_NUMBUF]; 23 int lib_inited; 24 static isc_mutex_t lib_mutex; 25 int ipv4_works; 26 int ipv6_works; 27 int debug; 28 29 /* 30 * initialization routine. Might be needed if the code is ROMized. 31 */ 32 void init_lib(void)33init_lib(void) 34 { 35 u_int u; 36 37 if (lib_inited) { 38 return; 39 } 40 ipv4_works = (ISC_R_SUCCESS == isc_net_probeipv4()); 41 ipv6_works = (ISC_R_SUCCESS == isc_net_probeipv6()); 42 init_systime(); 43 /* 44 * Avoid -Wrestrict warnings by keeping a pointer to each buffer 45 * so the compiler can see copying from one buffer to another is 46 * not violating restrict qualifiers on, e.g. memcpy() args. 47 */ 48 for (u = 0; u < COUNTOF(lib_stringbuf); u++) { 49 lib_stringbuf[u] = lib_stringbuf_storage[u]; 50 } 51 isc_mutex_init(&lib_mutex); 52 lib_inited = TRUE; 53 } 54 55 56 char * lib_getbuf(void)57lib_getbuf(void) 58 { 59 static int lib_nextbuf; 60 int mybuf; 61 62 if (!lib_inited) { 63 init_lib(); 64 } 65 isc_mutex_lock(&lib_mutex); 66 mybuf = lib_nextbuf; 67 lib_nextbuf = (1 + mybuf) % COUNTOF(lib_stringbuf); 68 isc_mutex_unlock(&lib_mutex); 69 zero_mem(lib_stringbuf[mybuf], LIB_BUFLENGTH); 70 71 return lib_stringbuf[mybuf]; 72 }