#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
+#include <assert.h>
#include "putty.h"
-/* My own versions of malloc, realloc and free. Because I want malloc and
- * realloc to bomb out and exit the program if they run out of memory,
- * realloc to reliably call malloc if passed a NULL pointer, and free
- * to reliably do nothing if passed a NULL pointer. Of course we can also
- * put trace printouts in, if we need to. */
+/*
+ * Generic routines to deal with send buffers: a linked list of
+ * smallish blocks, with the operations
+ *
+ * - add an arbitrary amount of data to the end of the list
+ * - remove the first N bytes from the list
+ * - return a (pointer,length) pair giving some initial data in
+ * the list, suitable for passing to a send or write system
+ * call
+ * - return the current size of the buffer chain in bytes
+ */
+
+#define BUFFER_GRANULE 512
+
+struct bufchain_granule {
+ struct bufchain_granule *next;
+ int buflen, bufpos;
+ char buf[BUFFER_GRANULE];
+};
+
+void bufchain_init(bufchain *ch)
+{
+ ch->head = ch->tail = NULL;
+ ch->buffersize = 0;
+}
+
+void bufchain_clear(bufchain *ch)
+{
+ struct bufchain_granule *b;
+ while (ch->head) {
+ b = ch->head;
+ ch->head = ch->head->next;
+ sfree(b);
+ }
+ ch->tail = NULL;
+ ch->buffersize = 0;
+}
+
+int bufchain_size(bufchain *ch)
+{
+ return ch->buffersize;
+}
+
+void bufchain_add(bufchain *ch, void *data, int len)
+{
+ char *buf = (char *)data;
+
+ ch->buffersize += len;
+
+ if (ch->tail && ch->tail->buflen < BUFFER_GRANULE) {
+ int copylen = min(len, BUFFER_GRANULE - ch->tail->buflen);
+ memcpy(ch->tail->buf + ch->tail->buflen, buf, copylen);
+ buf += copylen;
+ len -= copylen;
+ ch->tail->buflen += copylen;
+ }
+ while (len > 0) {
+ int grainlen = min(len, BUFFER_GRANULE);
+ struct bufchain_granule *newbuf;
+ newbuf = smalloc(sizeof(struct bufchain_granule));
+ newbuf->bufpos = 0;
+ newbuf->buflen = grainlen;
+ memcpy(newbuf->buf, buf, grainlen);
+ buf += grainlen;
+ len -= grainlen;
+ if (ch->tail)
+ ch->tail->next = newbuf;
+ else
+ ch->head = ch->tail = newbuf;
+ newbuf->next = NULL;
+ ch->tail = newbuf;
+ }
+}
+
+void bufchain_consume(bufchain *ch, int len)
+{
+ assert(ch->buffersize >= len);
+ assert(ch->head != NULL && ch->head->bufpos + len <= ch->head->buflen);
+ ch->head->bufpos += len;
+ ch->buffersize -= len;
+ if (ch->head->bufpos >= ch->head->buflen) {
+ struct bufchain_granule *tmp = ch->head;
+ ch->head = tmp->next;
+ sfree(tmp);
+ if (!ch->head)
+ ch->tail = NULL;
+ }
+}
+
+void bufchain_prefix(bufchain *ch, void **data, int *len)
+{
+ *len = ch->head->buflen - ch->head->bufpos;
+ *data = ch->head->buf + ch->head->bufpos;
+}
+
+/*
+ * My own versions of malloc, realloc and free. Because I want
+ * malloc and realloc to bomb out and exit the program if they run
+ * out of memory, realloc to reliably call malloc if passed a NULL
+ * pointer, and free to reliably do nothing if passed a NULL
+ * pointer. We can also put trace printouts in, if we need to; and
+ * we can also replace the allocator with an ElectricFence-like
+ * one.
+ */
+
+#ifdef MINEFIELD
+/*
+ * Minefield - a Windows equivalent for Electric Fence
+ */
+
+#define PAGESIZE 4096
+
+/*
+ * Design:
+ *
+ * We start by reserving as much virtual address space as Windows
+ * will sensibly (or not sensibly) let us have. We flag it all as
+ * invalid memory.
+ *
+ * Any allocation attempt is satisfied by committing one or more
+ * pages, with an uncommitted page on either side. The returned
+ * memory region is jammed up against the _end_ of the pages.
+ *
+ * Freeing anything causes instantaneous decommitment of the pages
+ * involved, so stale pointers are caught as soon as possible.
+ */
+
+static int minefield_initialised = 0;
+static void *minefield_region = NULL;
+static long minefield_size = 0;
+static long minefield_npages = 0;
+static long minefield_curpos = 0;
+static unsigned short *minefield_admin = NULL;
+static void *minefield_pages = NULL;
+
+static void minefield_admin_hide(int hide)
+{
+ int access = hide ? PAGE_NOACCESS : PAGE_READWRITE;
+ VirtualProtect(minefield_admin, minefield_npages * 2, access, NULL);
+}
+
+static void minefield_init(void)
+{
+ int size;
+ int admin_size;
+ int i;
+
+ for (size = 0x40000000; size > 0; size = ((size >> 3) * 7) & ~0xFFF) {
+ minefield_region = VirtualAlloc(NULL, size,
+ MEM_RESERVE, PAGE_NOACCESS);
+ if (minefield_region)
+ break;
+ }
+ minefield_size = size;
+
+ /*
+ * Firstly, allocate a section of that to be the admin block.
+ * We'll need a two-byte field for each page.
+ */
+ minefield_admin = minefield_region;
+ minefield_npages = minefield_size / PAGESIZE;
+ admin_size = (minefield_npages * 2 + PAGESIZE - 1) & ~(PAGESIZE - 1);
+ minefield_npages = (minefield_size - admin_size) / PAGESIZE;
+ minefield_pages = (char *) minefield_region + admin_size;
+
+ /*
+ * Commit the admin region.
+ */
+ VirtualAlloc(minefield_admin, minefield_npages * 2,
+ MEM_COMMIT, PAGE_READWRITE);
+
+ /*
+ * Mark all pages as unused (0xFFFF).
+ */
+ for (i = 0; i < minefield_npages; i++)
+ minefield_admin[i] = 0xFFFF;
+
+ /*
+ * Hide the admin region.
+ */
+ minefield_admin_hide(1);
+
+ minefield_initialised = 1;
+}
+
+static void minefield_bomb(void)
+{
+ div(1, *(int *) minefield_pages);
+}
+
+static void *minefield_alloc(int size)
+{
+ int npages;
+ int pos, lim, region_end, region_start;
+ int start;
+ int i;
+
+ npages = (size + PAGESIZE - 1) / PAGESIZE;
+
+ minefield_admin_hide(0);
+
+ /*
+ * Search from current position until we find a contiguous
+ * bunch of npages+2 unused pages.
+ */
+ pos = minefield_curpos;
+ lim = minefield_npages;
+ while (1) {
+ /* Skip over used pages. */
+ while (pos < lim && minefield_admin[pos] != 0xFFFF)
+ pos++;
+ /* Count unused pages. */
+ start = pos;
+ while (pos < lim && pos - start < npages + 2 &&
+ minefield_admin[pos] == 0xFFFF)
+ pos++;
+ if (pos - start == npages + 2)
+ break;
+ /* If we've reached the limit, reset the limit or stop. */
+ if (pos >= lim) {
+ if (lim == minefield_npages) {
+ /* go round and start again at zero */
+ lim = minefield_curpos;
+ pos = 0;
+ } else {
+ minefield_admin_hide(1);
+ return NULL;
+ }
+ }
+ }
+
+ minefield_curpos = pos - 1;
+
+ /*
+ * We have npages+2 unused pages starting at start. We leave
+ * the first and last of these alone and use the rest.
+ */
+ region_end = (start + npages + 1) * PAGESIZE;
+ region_start = region_end - size;
+ /* FIXME: could align here if we wanted */
+
+ /*
+ * Update the admin region.
+ */
+ for (i = start + 2; i < start + npages - 1; i++)
+ minefield_admin[i] = 0xFFFE; /* used but no region starts here */
+ minefield_admin[start + 1] = region_start % PAGESIZE;
+
+ minefield_admin_hide(1);
+
+ VirtualAlloc((char *) minefield_pages + region_start, size,
+ MEM_COMMIT, PAGE_READWRITE);
+ return (char *) minefield_pages + region_start;
+}
+
+static void minefield_free(void *ptr)
+{
+ int region_start, i, j;
+
+ minefield_admin_hide(0);
+
+ region_start = (char *) ptr - (char *) minefield_pages;
+ i = region_start / PAGESIZE;
+ if (i < 0 || i >= minefield_npages ||
+ minefield_admin[i] != region_start % PAGESIZE)
+ minefield_bomb();
+ for (j = i; j < minefield_npages && minefield_admin[j] != 0xFFFF; j++) {
+ minefield_admin[j] = 0xFFFF;
+ }
+
+ VirtualFree(ptr, j * PAGESIZE - region_start, MEM_DECOMMIT);
+
+ minefield_admin_hide(1);
+}
+
+static int minefield_get_size(void *ptr)
+{
+ int region_start, i, j;
+
+ minefield_admin_hide(0);
+
+ region_start = (char *) ptr - (char *) minefield_pages;
+ i = region_start / PAGESIZE;
+ if (i < 0 || i >= minefield_npages ||
+ minefield_admin[i] != region_start % PAGESIZE)
+ minefield_bomb();
+ for (j = i; j < minefield_npages && minefield_admin[j] != 0xFFFF; j++);
+
+ minefield_admin_hide(1);
+
+ return j * PAGESIZE - region_start;
+}
+
+static void *minefield_c_malloc(size_t size)
+{
+ if (!minefield_initialised)
+ minefield_init();
+ return minefield_alloc(size);
+}
+
+static void minefield_c_free(void *p)
+{
+ if (!minefield_initialised)
+ minefield_init();
+ minefield_free(p);
+}
+
+/*
+ * realloc _always_ moves the chunk, for rapid detection of code
+ * that assumes it won't.
+ */
+static void *minefield_c_realloc(void *p, size_t size)
+{
+ size_t oldsize;
+ void *q;
+ if (!minefield_initialised)
+ minefield_init();
+ q = minefield_alloc(size);
+ oldsize = minefield_get_size(p);
+ memcpy(q, p, (oldsize < size ? oldsize : size));
+ minefield_free(p);
+ return q;
+}
+
+#endif /* MINEFIELD */
#ifdef MALLOC_LOG
static FILE *fp = NULL;
-void mlog(char *file, int line) {
+void mlog(char *file, int line)
+{
if (!fp) {
fp = fopen("putty_mem.log", "w");
setvbuf(fp, NULL, _IONBF, BUFSIZ);
}
if (fp)
- fprintf (fp, "%s:%d: ", file, line);
+ fprintf(fp, "%s:%d: ", file, line);
}
#endif
-void *safemalloc(size_t size) {
- void *p = malloc (size);
+void *safemalloc(size_t size)
+{
+ void *p;
+#ifdef MINEFIELD
+ p = minefield_c_malloc(size);
+#else
+ p = malloc(size);
+#endif
if (!p) {
MessageBox(NULL, "Out of memory!", "PuTTY Fatal Error",
MB_SYSTEMMODAL | MB_ICONERROR | MB_OK);
return p;
}
-void *saferealloc(void *ptr, size_t size) {
+void *saferealloc(void *ptr, size_t size)
+{
void *p;
- if (!ptr)
- p = malloc (size);
- else
- p = realloc (ptr, size);
+ if (!ptr) {
+#ifdef MINEFIELD
+ p = minefield_c_malloc(size);
+#else
+ p = malloc(size);
+#endif
+ } else {
+#ifdef MINEFIELD
+ p = minefield_c_realloc(ptr, size);
+#else
+ p = realloc(ptr, size);
+#endif
+ }
if (!p) {
MessageBox(NULL, "Out of memory!", "PuTTY Fatal Error",
MB_SYSTEMMODAL | MB_ICONERROR | MB_OK);
return p;
}
-void safefree(void *ptr) {
+void safefree(void *ptr)
+{
if (ptr) {
#ifdef MALLOC_LOG
if (fp)
fprintf(fp, "free(%p)\n", ptr);
#endif
- free (ptr);
+#ifdef MINEFIELD
+ minefield_c_free(ptr);
+#else
+ free(ptr);
+#endif
}
#ifdef MALLOC_LOG
else if (fp)
fprintf(fp, "freeing null pointer - no action taken\n");
#endif
}
+
+#ifdef DEBUG
+static FILE *debug_fp = NULL;
+static int debug_got_console = 0;
+
+static void dputs(char *buf)
+{
+ DWORD dw;
+
+ if (!debug_got_console) {
+ AllocConsole();
+ debug_got_console = 1;
+ }
+ if (!debug_fp) {
+ debug_fp = fopen("debug.log", "w");
+ }
+
+ WriteFile(GetStdHandle(STD_OUTPUT_HANDLE), buf, strlen(buf), &dw,
+ NULL);
+ fputs(buf, debug_fp);
+ fflush(debug_fp);
+}
+
+
+void dprintf(char *fmt, ...)
+{
+ char buf[2048];
+ va_list ap;
+
+ va_start(ap, fmt);
+ vsprintf(buf, fmt, ap);
+ dputs(buf);
+ va_end(ap);
+}
+
+
+void debug_memdump(void *buf, int len, int L)
+{
+ int i;
+ unsigned char *p = buf;
+ char foo[17];
+ if (L) {
+ int delta;
+ dprintf("\t%d (0x%x) bytes:\n", len, len);
+ delta = 15 & (int) p;
+ p -= delta;
+ len += delta;
+ }
+ for (; 0 < len; p += 16, len -= 16) {
+ dputs(" ");
+ if (L)
+ dprintf("%p: ", p);
+ strcpy(foo, "................"); /* sixteen dots */
+ for (i = 0; i < 16 && i < len; ++i) {
+ if (&p[i] < (unsigned char *) buf) {
+ dputs(" "); /* 3 spaces */
+ foo[i] = ' ';
+ } else {
+ dprintf("%c%02.2x",
+ &p[i] != (unsigned char *) buf
+ && i % 4 ? '.' : ' ', p[i]
+ );
+ if (p[i] >= ' ' && p[i] <= '~')
+ foo[i] = (char) p[i];
+ }
+ }
+ foo[i] = '\0';
+ dprintf("%*s%s\n", (16 - i) * 3 + 2, "", foo);
+ }
+}
+
+#endif /* def DEBUG */
projects / u / mdw / putty / blobdiff