=================================================================== RCS file: /home/cvs/OpenXM_contrib2/asir2000/gc5.3/Attic/dyn_load.c,v retrieving revision 1.1 retrieving revision 1.2 diff -u -p -r1.1 -r1.2 --- OpenXM_contrib2/asir2000/gc5.3/Attic/dyn_load.c 2001/04/20 10:05:32 1.1 +++ OpenXM_contrib2/asir2000/gc5.3/Attic/dyn_load.c 2002/07/19 02:43:41 1.2 @@ -297,14 +297,209 @@ void GC_register_dynamic_libraries() # endif /* !USE_PROC ... */ # endif /* SUNOS */ -#if defined(LINUX) && defined(__ELF__) || defined(SCO_ELF) +#if defined(LINUX) && defined(__ELF__) || defined(SCO_ELF) || \ + (defined(NETBSD) && defined(__ELF__)) +#if 1 +/* #ifdef USE_PROC_FOR_LIBRARIES */ + +#include + +#include +#include +#include + +#define MAPS_BUF_SIZE (32*1024) + +extern ssize_t GC_repeat_read(int fd, char *buf, size_t count); + /* Repeatedly read until buffer is filled, or EOF is encountered */ + /* Defined in os_dep.c. */ + +static char *parse_map_entry(char *buf_ptr, word *start, word *end, + char *prot_buf, unsigned int *maj_dev); + +/* Repeatedly perform a read call until the buffer is filled or */ +/* we encounter EOF. */ +ssize_t GC_repeat_read(int fd, char *buf, size_t count) +{ + ssize_t num_read = 0; + ssize_t result; + + while (num_read < count) { + result = read(fd, buf + num_read, count - num_read); + if (result < 0) return result; + if (result == 0) break; + num_read += result; + } + return num_read; +} + +void GC_register_dynamic_libraries() +{ + int f; + int result; + char prot_buf[5]; + int maps_size; + char maps_temp[32768]; + char *maps_buf; + char *buf_ptr; + int count; + word start, end; + unsigned int maj_dev, min_dev; + word least_ha, greatest_ha; + unsigned i; + word datastart = (word)(DATASTART); + + /* Read /proc/self/maps */ + /* Note that we may not allocate, and thus can't use stdio. */ + f = open("/proc/self/maps", O_RDONLY); + if (-1 == f) ABORT("Couldn't open /proc/self/maps"); + /* stat() doesn't work for /proc/self/maps, so we have to + read it to find out how large it is... */ + maps_size = 0; + do { + result = GC_repeat_read(f, maps_temp, sizeof(maps_temp)); + if (result <= 0) ABORT("Couldn't read /proc/self/maps"); + maps_size += result; + } while (result == sizeof(maps_temp)); + + if (maps_size > sizeof(maps_temp)) { + /* If larger than our buffer, close and re-read it. */ + close(f); + f = open("/proc/self/maps", O_RDONLY); + if (-1 == f) ABORT("Couldn't open /proc/self/maps"); + maps_buf = alloca(maps_size); + if (NULL == maps_buf) ABORT("/proc/self/maps alloca failed"); + result = GC_repeat_read(f, maps_buf, maps_size); + if (result <= 0) ABORT("Couldn't read /proc/self/maps"); + } else { + /* Otherwise use the fixed size buffer */ + maps_buf = maps_temp; + } + + close(f); + maps_buf[result] = '\0'; + buf_ptr = maps_buf; + /* Compute heap bounds. Should be done by add_to_heap? */ + least_ha = (word)(-1); + greatest_ha = 0; + for (i = 0; i < GC_n_heap_sects; ++i) { + word sect_start = (word)GC_heap_sects[i].hs_start; + word sect_end = sect_start + GC_heap_sects[i].hs_bytes; + if (sect_start < least_ha) least_ha = sect_start; + if (sect_end > greatest_ha) greatest_ha = sect_end; + } + if (greatest_ha < (word)GC_scratch_last_end_ptr) + greatest_ha = (word)GC_scratch_last_end_ptr; + for (;;) { + + buf_ptr = parse_map_entry(buf_ptr, &start, &end, prot_buf, &maj_dev); + if (buf_ptr == NULL) return; + + if (prot_buf[1] == 'w') { + /* This is a writable mapping. Add it to */ + /* the root set unless it is already otherwise */ + /* accounted for. */ + if (start <= (word)GC_stackbottom && end >= (word)GC_stackbottom) { + /* Stack mapping; discard */ + continue; + } + if (start <= datastart && end > datastart && maj_dev != 0) { + /* Main data segment; discard */ + continue; + } +# ifdef THREADS + if (GC_segment_is_thread_stack(start, end)) continue; +# endif + /* The rest of this assumes that there is no mapping */ + /* spanning the beginning of the data segment, or extending */ + /* beyond the entire heap at both ends. */ + /* Empirically these assumptions hold. */ + + if (start < (word)DATAEND && end > (word)DATAEND) { + /* Rld may use space at the end of the main data */ + /* segment. Thus we add that in. */ + start = (word)DATAEND; + } + if (start < least_ha && end > least_ha) { + end = least_ha; + } + if (start < greatest_ha && end > greatest_ha) { + start = greatest_ha; + } + if (start >= least_ha && end <= greatest_ha) continue; + GC_add_roots_inner((char *)start, (char *)end, TRUE); + } + } +} + +// +// parse_map_entry parses an entry from /proc/self/maps so we can +// locate all writable data segments that belong to shared libraries. +// The format of one of these entries and the fields we care about +// is as follows: +// XXXXXXXX-XXXXXXXX r-xp 00000000 30:05 260537 name of mapping...\n +// ^^^^^^^^ ^^^^^^^^ ^^^^ ^^ +// start end prot maj_dev +// 0 9 18 32 +// +// The parser is called with a pointer to the entry and the return value +// is either NULL or is advanced to the next entry(the byte after the +// trailing '\n'.) +// +#define OFFSET_MAP_START 0 +#define OFFSET_MAP_END 9 +#define OFFSET_MAP_PROT 18 +#define OFFSET_MAP_MAJDEV 32 + +static char *parse_map_entry(char *buf_ptr, word *start, word *end, + char *prot_buf, unsigned int *maj_dev) +{ + int i; + unsigned int val; + char *tok; + + if (buf_ptr == NULL || *buf_ptr == '\0') { + return NULL; + } + + memcpy(prot_buf, buf_ptr+OFFSET_MAP_PROT, 4); // do the protections first + prot_buf[4] = '\0'; + + if (prot_buf[1] == 'w') { // we can skip all of this if it's not writable + + tok = buf_ptr; + buf_ptr[OFFSET_MAP_START+8] = '\0'; + *start = strtoul(tok, NULL, 16); + + tok = buf_ptr+OFFSET_MAP_END; + buf_ptr[OFFSET_MAP_END+8] = '\0'; + *end = strtoul(tok, NULL, 16); + + buf_ptr += OFFSET_MAP_MAJDEV; + tok = buf_ptr; + while (*buf_ptr != ':') buf_ptr++; + *buf_ptr++ = '\0'; + *maj_dev = strtoul(tok, NULL, 16); + } + + while (*buf_ptr && *buf_ptr++ != '\n'); + + return buf_ptr; +} + +#else /* !USE_PROC_FOR_LIBRARIES */ + /* Dynamic loading code for Linux running ELF. Somewhat tested on * Linux/x86, untested but hopefully should work on Linux/Alpha. * This code was derived from the Solaris/ELF support. Thanks to * whatever kind soul wrote that. - Patrick Bridges */ -#include +#if defined(NETBSD) +# include +#else +# include +#endif #include /* Newer versions of Linux/Alpha and Linux/x86 define this macro. We @@ -379,7 +574,9 @@ void GC_register_dynamic_libraries() } } -#endif +#endif /* !USE_PROC_FOR_LIBRARIES */ + +#endif /* LINUX */ #if defined(IRIX5) || defined(USE_PROC_FOR_LIBRARIES)