From 31d6f8bf94b77e6036671b6b96e3ee4bac5e5755 Mon Sep 17 00:00:00 2001 From: Randy Jordan Date: Thu, 1 Jan 2026 16:44:21 -0600 Subject: [PATCH] Initial commit --- LICENSE | 21 ++++++++++ Makefile | 76 ++++++++++++++++++++++++++++++++++ README.md | 28 +++++++++++++ include/except.h | 81 +++++++++++++++++++++++++++++++++++++ include/mem.h | 35 ++++++++++++++++ src/except.c | 30 ++++++++++++++ src/mem.c | 65 +++++++++++++++++++++++++++++ tests/01_malloc.c | 11 +++++ tests/02_calloc.c | 11 +++++ tests/03_malloc_softfail.c | 11 +++++ tests/04_malloc_exception.c | 28 +++++++++++++ tests/_ | 39 ++++++++++++++++++ 12 files changed, 436 insertions(+) create mode 100644 LICENSE create mode 100644 Makefile create mode 100644 README.md create mode 100644 include/except.h create mode 100644 include/mem.h create mode 100644 src/except.c create mode 100644 src/mem.c create mode 100644 tests/01_malloc.c create mode 100644 tests/02_calloc.c create mode 100644 tests/03_malloc_softfail.c create mode 100644 tests/04_malloc_exception.c create mode 100644 tests/_ diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..8aa2645 --- /dev/null +++ b/LICENSE @@ -0,0 +1,21 @@ +MIT License + +Copyright (c) [year] [fullname] + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..3b8792f --- /dev/null +++ b/Makefile @@ -0,0 +1,76 @@ +# Compiler Flags +CC := gcc +CFLAGS := -g -Wall -Wextra -Werror -pedantic -fsanitize=address,undefined -fno-omit-frame-pointer +export ASAN_OPTIONS = allocator_may_return_null=1 +# Directory variables +LIBDIR := lib +OBJ := obj +INC := include +SRC := src +TEST := tests + +# Filepath Pattern Matching +LIB := $(LIBDIR)/lib.a +SRCS := $(wildcard $(SRC)/*.c) +OBJS := $(patsubst $(SRC)/%.c, $(OBJ)/%.o, $(SRCS)) +TESTS := $(wildcard $(TEST)/*.c) +TESTBINS := $(patsubst $(TEST)/%.c, $(TEST)/bin/%, $(TESTS)) + +# Commands must be labeled PHONY +.PHONY: all release clean test + +# Compiler Release Flags +release: CFLAGS := -Wall -Wextra -Werror -pedantic -fsanitize=address,undefined -fno-omit-frame-pointer -O2 -DNDEBUG +release: clean $(LIB) + +# Target for compilation. +all: $(LIB) + +# Target / Dependencies +$(LIB): $(OBJS) | $(LIBDIR) + $(RM) $(LIB) + ar -cvrs $@ $^ + +$(OBJ)/%.o: $(SRC)/%.c $(SRC)/%.h | $(OBJ) + $(CC) $(CFLAGS) -c $< -o $@ + +$(OBJ)/%.o: $(SRC)/%.c | $(OBJ) + $(CC) $(CFLAGS) -c $< -o $@ + +$(TEST)/bin/%: $(TEST)/%.c $(LIB) | $(TEST)/bin + $(CC) $(CFLAGS) $< $(LIB) -o $@ + +# Make directories if none. +$(LIBDIR): + mkdir $@ + +$(INC): + mkdir $@ + +$(OBJ): + mkdir $@ + +$(TEST)/bin: + mkdir $@ + +# Run the tests in the bin folder and track results +test: $(LIB) $(TEST)/bin $(TESTBINS) + @SUCCESS_COUNT=0; FAILURE_COUNT=0; \ + for test in $(TESTBINS); do \ + ./$$test; \ + EXIT_CODE=$$?; \ + TEST_NAME=$(notdir $$test); \ + if [ $$EXIT_CODE -eq 0 ]; then \ + echo "\033[0;32m$$TEST_NAME: EXIT CODE: $$EXIT_CODE (SUCCESS)\033[0m"; \ + SUCCESS_COUNT=$$((SUCCESS_COUNT + 1)); \ + else \ + echo "\033[0;31m$$TEST_NAME: EXIT CODE: $$EXIT_CODE (FAILURE)\033[0m"; \ + FAILURE_COUNT=$$((FAILURE_COUNT + 1)); \ + fi; \ + done; \ + echo "\n\nTests completed"; \ + echo "SUCCESS: $$SUCCESS_COUNT"; \ + echo "FAILURE: $$FAILURE_COUNT"; + +clean: + $(RM) -r $(LIBDIR) $(OBJ) $(TEST)/bin/ diff --git a/README.md b/README.md new file mode 100644 index 0000000..11b6252 --- /dev/null +++ b/README.md @@ -0,0 +1,28 @@ +# mem + +## Description +Simple memory allocator written in C. + +## Table of Contents + +- [Description](#description) +- [Features](#features) +- [Usage](#usage) +- [Credits / Resources](#credits--resources) +- [License](#license) + +## Features / TODOS +- [x] Try / Catch +- [x] Versatile Error Handling + +## Usage +`make` to build.
+`make test` to build and run tests. ASAN allocator may fail option is turned on to showcase failure handling.
+ +## Credits / Resources +[Memory Allocation Strategies - Ginger Bill](https://www.gingerbill.org/series/memory-allocation-strategies/)
+[Arena allocator tips and tricks - Chris Wellons](https://nullprogram.com/blog/2023/09/27/)
+[C Interfaces and Implementations](https://github.com/drh/cii)
+ +## License +This project is licensed under MIT - see the [LICENSE](LICENSE) file for details. diff --git a/include/except.h b/include/except.h new file mode 100644 index 0000000..dd3712d --- /dev/null +++ b/include/except.h @@ -0,0 +1,81 @@ +#ifndef EXCEPT_INCLUDED +#define EXCEPT_INCLUDED + +#include +#define UNUSED(x) (void)(x) + +struct Exception { + const char *reason; +}; +typedef struct Exception Exception; + +struct ExceptFrame { + struct ExceptFrame *prev; // Exception Stack + jmp_buf env; // Enviroment Buffer + const char *file; // Exception File + int line; // Exception Line + const Exception *exception; // Exception Reason +}; +typedef struct ExceptFrame ExceptFrame; + +// Exception States +enum { EXCEPT_ENTERED=0, EXCEPT_RAISED, EXCEPT_HANDLED, EXCEPT_FINALIZED}; + +void except_raise(const Exception *e, const char *file,int line); // Raise exceptions + +// External declarations +extern ExceptFrame *except_stack; // Global exception stack +extern const Exception assert_failed; // Forward declaration for assert. +extern void asserted(int e); + +#ifdef NDEBUG +#define ASSERTED(e) ((void)0) +#else +#define ASSERTED(e) ((void)((e)||(RAISE(assert_failed),0))) +#endif + +// Raise an Exception. +#define RAISE(e) except_raise(&(e), __FILE__, __LINE__) + +// Reraise the currect exception. +#define RERAISE except_raise(except_frame.exception, \ + except_frame.file, except_frame.line) + +// Switch to the previous exception frame and return. +#define RETURN switch (except_stack = except_stack->prev,0) default: return + +// Start a try block. +#define TRY do { \ + volatile int except_flag; \ + ExceptFrame except_frame; \ + except_frame.prev = except_stack; \ + except_stack = &except_frame; \ + except_flag = setjmp(except_frame.env); \ + if (except_flag == EXCEPT_ENTERED) { + +// Handle specific example. +#define EXCEPT(e) \ + if (except_flag == EXCEPT_ENTERED) except_stack = except_stack->prev; \ + } else if (except_frame.exception == &(e)) { \ + except_flag = EXCEPT_HANDLED; + +// Catch all other exceptions. +#define ELSE \ + if (except_flag == EXCEPT_ENTERED) except_stack = except_stack->prev; \ + } else { \ + except_flag = EXCEPT_HANDLED; + +// Execute finalization code. +#define FINALLY \ + if (except_flag == EXCEPT_ENTERED) except_stack = except_stack->prev; \ + } { \ + if (except_flag == EXCEPT_ENTERED) \ + except_flag = EXCEPT_FINALIZED; + +// End Try block. +#define END_TRY \ + if (except_flag == EXCEPT_ENTERED) except_stack = except_stack->prev; \ + } if (except_flag == EXCEPT_RAISED) RERAISE; \ +} while (0) + +#endif diff --git a/include/mem.h b/include/mem.h new file mode 100644 index 0000000..241741d --- /dev/null +++ b/include/mem.h @@ -0,0 +1,35 @@ +#ifndef MEM_INCLUDED +#define MEM_INCLUDED + +#include "except.h" // Exceptions +#include // size_t + +/* General Macros*/ +#define MEM_KB(x) ((size_t)(x) * 1024ULL) +#define MEM_MB(x) ((size_t)(x) * 1024ULL * 1024ULL) +#define MEM_GB(x) ((size_t)(x) * 1024ULL * 1024ULL * 1024ULL) +#define MEM_SIZE(x) (ptrdiff_t)sizeof(x) +#define MEM_COUNT(a) (MEM_SIZE(a) / MEM_SIZE(*(a))) +#define MEM_LEN(s) (MEM_COUNT(s) - 1) + +/* Default behavior is to throw exceptions and zero out memory*/ +enum MemFlags { + NOZERO = 1 << 0, /* 0001 */ + SOFT_FAIL = 1 << 1, /* 0010 */ + HARD_FAIL = 1 << 2, /* 0100 */ +}; + +extern const Exception OOM; // Out of memory + +extern void *mem_alloc (int flags, size_t nbytes, const char *file, int line); +extern void mem_free(void *ptr, const char *file, int line); +extern void *mem_resize(int flags, void *ptr, size_t nbytes, const char *file, int line); +extern int mem_is_zero(const void *ptr, size_t nbytes); + + +#define ALLOC(flags, nbytes) mem_alloc((flags), (nbytes), __FILE__, __LINE__) +#define FREE(ptr) ((void)(mem_free((ptr), __FILE__, __LINE__), (ptr) = 0)) +#define RESIZE(flags, ptr, nbytes) ((ptr) = mem_resize((flags), (ptr), \ + (nbytes), __FILE__, __LINE__)) + +#endif diff --git a/src/except.c b/src/except.c new file mode 100644 index 0000000..ecadde7 --- /dev/null +++ b/src/except.c @@ -0,0 +1,30 @@ +#include "../include/except.h" +#include +#include + +ExceptFrame *except_stack = NULL; // Global exception stack. +const Exception assert_failed = { "Assertion Failure!" }; // If ASSERT fails. + +void except_raise(const Exception *e, const char *file,int line) { + // An exception was raised, grab the exception stack. + ExceptFrame *p = except_stack; + asserted(e != NULL); // Ensure exception pointer is not NULL + if (p == NULL) { // Uncaught Exception + const char *msg = e->reason ? e->reason : "Uncaught Exception!"; + fprintf(stderr,"\033[31m%s | Address: 0x%p | Raised at %s@%d \033[0m" ,msg,(void *)e,file,line); + fflush(stderr); + abort(); + } + // Set the exception details to the current frame. + p->exception = e; // Exception reason + p->file = file; + p->line = line; + // Move to the previous frame in the stack. + except_stack = except_stack->prev; + // Jump to the saved context environment. + longjmp(p->env, EXCEPT_RAISED); +} +void asserted(int e) { + ASSERTED(e); + UNUSED(e); +} diff --git a/src/mem.c b/src/mem.c new file mode 100644 index 0000000..7e640d8 --- /dev/null +++ b/src/mem.c @@ -0,0 +1,65 @@ +#include +#include +#include +#include "../include/except.h" +#include "../include/mem.h" + +const Exception OOM = { "Out of Memory" }; +#define MEM_ENOMEM 12 + +void *mem_alloc(int flags, size_t nbytes, const char *file, int line){ + void *ptr; + ASSERTED(nbytes > 0); + ptr = malloc(nbytes); + if (ptr == NULL){ // OOM check flags for how to handle. + if (flags & SOFT_FAIL) return 0; + if (flags & HARD_FAIL) exit(MEM_ENOMEM); + + if (file == NULL) // Wasn't called by macro + RAISE(OOM); // Out of Memory Exception + else // Called by macro + except_raise(&OOM, file, line); + } + return flags&NOZERO ? ptr : memset(ptr, 0, nbytes); +} + +void mem_free(void *ptr, const char *file, int line) { + UNUSED(file); + UNUSED(line); + if (ptr){ + free(ptr); + } +} + +void *mem_resize(int flags, void *ptr, size_t nbytes,const char *file, int line) { + ASSERTED(ptr); + ASSERTED(nbytes > 0); + ptr = realloc(ptr, nbytes); + if (ptr == NULL){ // OOM check flags for how to handle. + if(flags & SOFT_FAIL) return 0; + if(flags & HARD_FAIL) exit(MEM_ENOMEM); + + if (file == NULL) // Wasn't called by macro + RAISE(OOM); // Out of memory exception + else // Called by macro + except_raise(&OOM, file, line); + } + return ptr; +} + +int mem_is_zero(const void *ptr, size_t nbytes) { + ASSERTED(ptr); + ASSERTED(nbytes > 0); + static const unsigned char zero_block[1024] = {0}; + while (nbytes >= sizeof(zero_block)) { + if (memcmp(ptr, zero_block, sizeof(zero_block)) != 0) + return 0; + ptr = (const unsigned char *)ptr + sizeof(zero_block); + nbytes -= sizeof(zero_block); + } + if (nbytes > 0 && memcmp(ptr, zero_block, nbytes) != 0) + return 0; + return 1; +} + + diff --git a/tests/01_malloc.c b/tests/01_malloc.c new file mode 100644 index 0000000..ead898f --- /dev/null +++ b/tests/01_malloc.c @@ -0,0 +1,11 @@ +#define DEBUG +#include +#include "../include/mem.h" + +int main(void){ + size_t nbytes = 20; + void *ptr = ALLOC(0, nbytes); + ASSERTED(ptr != NULL); + ASSERTED( mem_is_zero(ptr, nbytes)); + return EXIT_SUCCESS; +} diff --git a/tests/02_calloc.c b/tests/02_calloc.c new file mode 100644 index 0000000..6aa0f16 --- /dev/null +++ b/tests/02_calloc.c @@ -0,0 +1,11 @@ +#define DEBUG +#include +#include "../include/mem.h" + +int main(void){ + size_t nbytes = 20; + void *ptr = ALLOC(NOZERO, nbytes); + ASSERTED(ptr != NULL); + ASSERTED( !mem_is_zero(ptr, nbytes)); + return EXIT_SUCCESS; +} diff --git a/tests/03_malloc_softfail.c b/tests/03_malloc_softfail.c new file mode 100644 index 0000000..3e78c5a --- /dev/null +++ b/tests/03_malloc_softfail.c @@ -0,0 +1,11 @@ +#define DEBUG +#include +#include +#include "../include/mem.h" + +int main(void){ + size_t nbytes = MEM_GB(1024); + void *ptr = ALLOC(SOFT_FAIL, nbytes); + ASSERTED(ptr == NULL); + return EXIT_SUCCESS; +} diff --git a/tests/04_malloc_exception.c b/tests/04_malloc_exception.c new file mode 100644 index 0000000..7d0bb71 --- /dev/null +++ b/tests/04_malloc_exception.c @@ -0,0 +1,28 @@ +#define DEBUG +#include +#include +#include +#include "../include/mem.h" + +int main(void){ + size_t nbytes = MEM_GB(1024); + void *buf; + TRY { + buf = ALLOC(0,nbytes); /* try 1GB */ + if (!buf) + RAISE(OOM); + free(buf); + } + EXCEPT(OOM) { + /* handle memory failure gracefully */ + fprintf(stderr, "Caught: %s\n", OOM.reason); + return EXIT_SUCCESS; /* requested behavior */ + } + FINALLY { + /* cleanup if needed, runs always */ + if (buf) free(buf); + } + END_TRY; + + return EXIT_FAILURE; /* shouldn't reach here for this example */ + } diff --git a/tests/_ b/tests/_ new file mode 100644 index 0000000..574503e --- /dev/null +++ b/tests/_ @@ -0,0 +1,39 @@ +#define DEBUG +#include +#include +#include "../include/mem.h" +#include +int main(void){ + size_t count = 20; + size_t nbytes = sizeof(int32_t) * count; + struct Arena_Type mem = ARENA_TYPE(HARD_FAIL, ARENA_INT_32, count); + ASSERTED(mem.buf.beg != NULL); + ASSERTED( mem_is_zero(mem.buf.beg, nbytes)); + ASSERTED( (size_t)(mem.buf.end - mem.buf.beg) == nbytes); + size_t size = (size_t)(mem.buf.end - mem.buf.beg); + ASSERTED(mem.header.type != arena_id_to_header[ARENA_UINT_32]); + ASSERTED(mem.header.type == arena_id_to_header[ARENA_INT_32]); + ASSERTED(mem.was_malloc == 1); + (void) size; + /* + printf("Bytes: %ld\t Alignment: %ld\t Type_Size: %ld\t Type_ID: %d\t Type_Header:%c\n", + size, size/count, size/count, mem.header.type, mem.header.type); + */ + unsigned char *ptr = mem.buf.beg; + int32_t *arr = ARENA_ALLOC(0, &mem.buf, sizeof(int32_t), sizeof(int32_t), count); + for (int i = 0; i < 20; i++){ + arr[i] = rand(); + } + ASSERTED(ptr != NULL); + + char template[] = "/tmp/intfileXXXXXX"; + int fd; + fd = mkstemp(template); + write(fd, ptr, nbytes); + lseek(fd,0,SEEK_SET); + unsigned char buf[nbytes]; + ssize_t bytesread = read(fd, buf, nbytes); + printf("Read %ld bytes\n",bytesread); + free(ptr); + return EXIT_SUCCESS; +}