AmendHub

--- util.c Thu Feb 1 17:37:17 2024 +++ util.c Thu Feb 15 15:18:31 2024 @@ -107,18 +107,112 @@ util_init(void) #define MUL_NO_OVERFLOW ((size_t)1 << (sizeof(size_t) * 4)) +#ifdef MALLOC_DEBUG + +#define SYMBOL_SIZE 32 +static char symbols[64][SYMBOL_SIZE]; + +#define MAX_STACK_DEPTH 10 +struct xalloc { + char *stack[MAX_STACK_DEPTH]; + unsigned long addr; + unsigned long size; +}; +static struct xalloc xallocs[256] = { 0 }; +#endif + void * xmalloc(size_t size) { void *ptr; - +#ifdef MALLOC_DEBUG + char tsym[SYMBOL_SIZE], *sym; + struct xalloc *xa; + unsigned long _a6, ret; + unsigned char *code; + size_t n, cn, j; + short nframe; +#endif + if (size == 0) panic("xmalloc: zero size"); ptr = NewPtr(size); -#if 0 if (ptr == NULL) - warn("Insufficient memory available: xmalloc(%lu) failed", size); + return NULL; + +#ifdef MALLOC_DEBUG + asm { + move.l a6,_a6 + }; + + xa = NULL; + for (n = 0; n < nitems(xallocs); n++) { + if (xallocs[n].addr == 0) { + xa = &xallocs[n]; + break; + } + } + if (xa == NULL) + panic("out of xalloc space"); + + /* + * A6 register points to previous stack A6. Above A6 is our return + * address. Walk the code after the return address looking for an RTS + * instruction, then walk 3 bytes after that and we should have that + * function's symbol. Then jump to the previous A6 that our A6 points + * to and do it again to find the previous function symbol, repeating + * until we hit "main" or "uthread_begin". + */ + for (nframe = 0; nframe < MAX_STACK_DEPTH; nframe++) { + ret = *(unsigned long *)(_a6 + 4); + code = (unsigned char *)ret; + + tsym[0] = '\0'; + for (; ; code += 2) { + if (code[0] == 0x4e && code[1] == 0x75) { /* RTS */ + code += 3; + strlcpy(tsym, (char *)code, sizeof(tsym)); + break; + } + } + + if (!tsym[0]) + break; + + sym = NULL; + for (n = 0; n < nitems(symbols); n++) { + if (symbols[n][0] == '\0') + break; + if (strcmp(symbols[n], tsym) == 0) { + sym = (char *)&symbols[n]; + break; + } + } + if (sym == NULL) { + for (n = 0; n < nitems(symbols); n++) { + if (symbols[n][0] != '\0') + continue; + + strlcpy(symbols[n], tsym, sizeof(symbols[n])); + sym = (char *)&symbols[n]; + break; + } + } + if (sym == NULL) + break; + + xa->stack[nframe] = sym; + + if (strcmp(sym, "main") == 0 || strcmp(sym, "uthread_begin") == 0) + break; + + /* walk back up the chain */ + _a6 = *(unsigned long *)_a6; + } + + xa->addr = (unsigned long)ptr; + xa->size = size; #endif return ptr; @@ -129,6 +223,9 @@ xfree(void *ptrptr) { unsigned long *addr = (unsigned long *)ptrptr; void *ptr; +#ifdef MALLOC_DEBUG + size_t n; +#endif if (ptrptr == NULL) panic("xfree(NULL)"); @@ -136,7 +233,19 @@ xfree(void *ptrptr) ptr = (void *)*addr; if (ptr == NULL) panic("xfree(&NULL) likely a double-free"); - + +#ifdef MALLOC_DEBUG + for (n = 0; n < nitems(xallocs); n++) { + if (xallocs[n].addr == (unsigned long)ptr) { + memset(&xallocs[n], 0, sizeof(xallocs[n])); + break; + } + } + if (n == nitems(xallocs)) + panic("xfree() without xalloc, possibly a junk free", + (unsigned long)ptr); +#endif + DisposePtr(ptr); *addr = 0L; } @@ -222,6 +331,48 @@ xstrndup(const char *str, size_t maxlen) return copy; } + +#ifdef MALLOC_DEBUG +void +xalloc_print(size_t (*printer)(const char *, ...)) +{ + ssize_t n, j, len; + size_t total = 0, nallocs = 0; + char chain[128]; + + for (n = 0; n < nitems(xallocs); n++) { + if (xallocs[n].addr == 0) + continue; + + total += xallocs[n].size; + nallocs++; + + chain[0] = '\0'; + len = 0; + for (j = MAX_STACK_DEPTH - 1; j >= 0; j--) { + if (xallocs[n].stack[j] == 0) + continue; + + if (chain[0] != '\0') { + if (len >= sizeof(chain) - 2) + break; + chain[len++] = ' '; + chain[len++] = ':'; + chain[len++] = ' '; + chain[len++] = '\0'; + } + + len = strlcat(chain, xallocs[n].stack[j], sizeof(chain)); + if (len >= sizeof(chain)) + break; + } + + printer("%ld @ %s", xallocs[n].size, chain); + } + + printer("%ld bytes in %ld allocations in use", total, nallocs); +} +#endif /* if var having used_size can't fit add, grow it by grow_amount */ bool --- util.h Thu Feb 1 17:37:30 2024 +++ util.h Thu Feb 15 15:29:35 2024 @@ -21,6 +21,9 @@ #include <limits.h> #include <time.h> +/* uncomment to enable malloc tracking */ +// #define MALLOC_DEBUG + #ifndef SIZE_MAX #define SIZE_MAX ULONG_MAX #endif @@ -28,8 +31,6 @@ #define nitems(what) (sizeof((what)) / sizeof((what)[0])) #define member_size(type, member) sizeof(((type *)0)->member) -#define MALLOC_NOTE_SIZE 32 - #define MIN(a, b) ((a) < (b) ? (a) : (b)) #define MAX(a, b) ((a) > (b) ? (a) : (b)) #define BOUND(a, min, max) ((a) > (max) ? (max) : ((a) < (min) ? (min) : (a))) @@ -93,6 +94,9 @@ void * xrealloc(void *src, size_t size); void * xreallocarray(void *, size_t, size_t); char * xstrdup(const char *); char * xstrndup(const char *str, size_t maxlen); +#ifdef MALLOC_DEBUG +void xalloc_print(size_t (*printer)(const char *, ...)); +#endif bool grow_to_fit(void *var, size_t *var_size, size_t used_size, size_t add, size_t grow_amount);