Added stuff to CHANGELOG for v1.0

It has been solved!!!

.gitignore

@@ -1,3 +1,9 @@
 # Ignore build files
 build/*
 !build/.keep
+
+# Ignore documentation
+doc/
+
+# Ignore vim temporary files
+*.sw[a-z]

.gitlab-ci.yml

@@ -2,12 +2,19 @@ image: gcc
 
 build:
     stage: build
+    # Install dependencies
     before_script:
-        - apt update && apt -y install cmake
+        - apt update && apt -y install cmake libgmp-dev libgomp1
+    # Build the project
     script:
         - cd build/
         - cmake -DCMAKE_BUILD_TYPE=Release ..
         - make
+    # Find the resulting binary
     artifacts:
         paths:
             - build/indivisible
+    # Cache .o files for faster compiling
+    cache:
+        paths:
+            - "build/CMakeFiles/indivisible.dir/src/*.o"

CHANGELOG

@@ -4,4 +4,35 @@ Change Log
 - v0.1: Initial release
 	- Basic prime calculation.
 	- Uses a growing vector of known primes and gets the modulus of the number divided by these primes.
-	- Uses type `long long` to hold prime numbers.
+	- Uses type `long long' to hold prime numbers.
+- v0.2: Multi-Precision
+	- Switch to C.
+	- Uses GNU Multiple Precision library (GMP) to hold prime numbers, allowing for 'infinite' size.
+	- Add `likely()' and `unlikely()' macros to optimize.
+- v0.2.1: Memory Leak Fixes
+	- Fixed a major memory leak at the end of the program.
+	- Added more optimizers.
+- v0.3: Optimizations
+	- Algorithm skips half the known primes.
+	- Removed `likely()' and `unlikely()' macros due to lack of information.
+	- Improved performance.
+- v0.4: Fixed Algorithm
+	- Fixed algorithm to actually calculate primes.
+	- Added extra C99 optimizations.
+- v0.5: Minor Changes
+	- Use `size_t' instead of `unsigned long long int'.
+	- Minor optimizations to the algorithm.
+	- Added commandline argument parsing.
+- v0.6: User Control
+	- Allow user to choose base in which the prime numbers are printed.
+	- Give option for primes to be saved to a file upon exit.
+	- Free memory and leave instead of emergency exit.
+- v0.7: Data Saving
+	- Allow user to save found primes to be loaded later.
+	- User can save and read primes in raw output.
+- v1.0: Parallelization
+	- Now completely parallelized.
+	- Cleaned up/organized the code-base
+	- Exporting files uses less memory
+	- Allow searching for the nth prime number
+	- Clearing some memory leaks

CMakeLists.txt

@@ -1,23 +1,41 @@
 cmake_minimum_required(VERSION 2.6)
 project(Indivisible)
 
+cmake_policy(SET CMP0012 OLD)
+
 set(TARGET_NAME indivisible)
 
 if(NOT CMAKE_BUILD_TYPE)
 	set(CMAKE_BUILD_TYPE Debug)
 endif()
 
-set(SRCS
-    src/Main.cpp)
+set(CMAKE_MODULE_PATH
+	${CMAKE_MODULE_PATH}
+	${CMAKE_SOURCE_DIR}/cmake/)
 
-set(CMAKE_CXX_FLAGS "-std=c++14 -fno-elide-constructors -pedantic-errors -Wall -Wextra -Werror -Wpedantic -Winit-self -Wmissing-declarations -Wuninitialized -Wfatal-errors")
-set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS} -O3")
-set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS} -g -O0")
-set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_CXX_FLAGS} -g -O3")
-set(CMAKE_CXX_FLAGS_MINSIZEREL "${CMAKE_CXX_FLAGS} -Os")
+find_package(GMP REQUIRED)
+find_package(OpenMP REQUIRED)
+
+include_directories(
+	${GMP_INCLUDE_DIR})
+
+set(SRCS
+	src/main.c
+	src/files.c
+	src/list.c)
+
+# Define the C flags.
+set(CMAKE_C_FLAGS "-std=gnu99 ${OpenMP_C_FLAGS} -Wall -Wextra -Werror -Wfatal-errors -Wmissing-declarations -pedantic-errors")
+set(CMAKE_C_FLAGS_DEBUG "-g -O0")
+set(CMAKE_C_FLAGS_RELEASE "-O3")
+set(CMAKE_C_FLAGS_RELWITHDEBINFO "-g -O3")
+set(CMAKE_C_FLAGS_MINSIZEREL "-Os")
 
 if(NOT CMAKE_BUILD_TYPE MATCHES Debug AND NOT CMAKE_BUILD_TYPE MATCHES RelWithDebInfo)
 	add_definitions(-DNDEBUG)
 endif()
 
 add_executable(${TARGET_NAME} ${SRCS})
+
+target_link_libraries(${TARGET_NAME}
+	${GMP_LIBRARY})

CONTRIBUTING.md

@@ -1,6 +1,6 @@
 Contributing
 ============
-We gladly accept contributions to Indivisible, however there are a few guidelines that must be followed.
+We gladly accept contributions to Indivisible (send Git patches to <deathsbreed@themusicinnoise.net>), however there are a few guidelines that must be followed.
 
 1) Copyright & Licensing
 ------------------------
@@ -8,7 +8,7 @@ The copyright of this project and all of its code, unless stated otherwise, belo
 
 2) Documentation
 ----------------
-All new features added must be well documented using DOxygen style comments. If your merge request adds a new feature and it is not well documented we will ask you to finish documenting the code before accepting a merge. This is simply so that both the maintainers of this repo and other users can understand the new API that bas been added.
+All new features added must be well documented using DOxygen style comments. If your patch adds a new feature and it is not well documented we will ask you to finish documenting the code before accepting a patch. This is simply so that both the maintainers of this repo and other users can understand the new API that bas been added.
 
 3) Code-Style
 -------------
@@ -16,8 +16,8 @@ The only aspects that will be religiously upheld for all contributions to this r
 
 Things that would be nice is if you could avoid having the lines being too long, and please avoid having more than one empty line in a row.
 
-4) Fractured Merge Requests
----------------------------
-Please make sure your merge requests are fractured into separate parts so that it may be easy for us to deal with them individually. The reason for this is to avoid having merge requests that both fix bugs and add features when in reality they should be separate requests. The only exception to this will be if the changes made to the code depend on one another to function properly.
+4) Fractured Patches
+--------------------
+Please make sure your patches are fractured into separate parts so that it may be easy for us to deal with them individually. The reason for this is to avoid having patches that both fix bugs and add features when in reality they should be separate requests. The only exception to this will be if the changes made to the code depend on one another to function properly.
 
-If your merge request meets all these requirements and is passed by one of the moderators it will be merged into the main repo.
+If your patch meets all these requirements and is passed by one of the moderators it will be merged into the main repo.

README.md

@@ -2,12 +2,16 @@ Indivisible
 ===========
 [![build status](https://gitlab.com/Deathsbreed/Indivisible/badges/master/build.svg)](https://gitlab.com/Deathsbreed/Indivisible/commits/master)
 
-Indivisible is an optimized prime number generator written in C++.
+Indivisible is an optimized prime number generator written in C.
 
 Building
 --------
-This project uses CMake to build.
+There are multiple dependencies to install before compiling the project:
+- CMake
+- GMP
+- OpenMP
 
+Once the dependencies are installed you can compile by running the following from the root directory of the project:
 ```bash
 $ cd build/
 $ cmake ..
@@ -18,7 +22,7 @@ To build a release build run `cmake -DCMAKE_BUILD_TYPE=Release ..` instead.
 
 Contributing
 ------------
-If you would like to contribute to Uhn then please read the [contributing file](/CONTRIBUTING.md) before creating a merge request.
+If you would like to contribute to Indivisible then please read the [contributing file](/CONTRIBUTING.md) before sending a patch. You may send the patches to <deathsbreed@themusicinnoise.net>.
 
 License
 -------

cmake/FindGMP.cmake

@@ -0,0 +1,24 @@
+# SOURCE: http://stackoverflow.com/questions/29307862/error-linking-gmp-library
+set(GMP_PREFIX "" CACHE PATH "path ")
+
+find_path(GMP_INCLUDE_DIR gmp.h gmpxx.h
+	PATHS ${GMP_PREFIX}/include /usr/include /usr/local/include )
+
+find_library(GMP_LIBRARY NAMES gmp libgmp
+	PATHS ${GMP_PREFIX}/lib /usr/lib /usr/local/lib)
+
+
+if(GMP_INCLUDE_DIR AND GMP_LIBRARY)
+	get_filename_component(GMP_LIBRARY_DIR ${GMP_LIBRARY} PATH)
+	set(GMP_FOUND TRUE)
+endif()
+
+if(GMP_FOUND)
+	if(NOT GMP_FIND_QUIETLY)
+		MESSAGE(STATUS "Found GMP: ${GMP_LIBRARY}")
+	endif()
+else()
+	if(GMP_FIND_REQUIRED)
+		message(FATAL_ERROR "Could not find GMP")
+	endif()
+endif()

src/Main.cpp

@@ -1,38 +0,0 @@
-#include <iostream>
-#include <vector>
-#include <csignal>
-
-static bool run;
-
-void leave(int signum);
-
-int main(void) {
-	std::cout << "Indivisible v0.1\n";
-	run = true;
-
-	signal(SIGINT, leave);
-
-	std::vector<unsigned long long> primes;
-	primes.push_back(2);
-	unsigned long long num = 2;
-
-	while(run) {
-		bool isPrime = true;
-		for(auto i : primes) {
-			if(i > num / 2) break;
-			if(num % i == 0) isPrime = false;
-		}
-		if(isPrime) {
-			primes.push_back(num);
-			std::cout << num << std::endl;
-		}
-		++num;
-	}
-
-	return 0;
-}
-
-void leave(int signum) {
-	std::cout << "Exiting (" << signum << ")\n";
-	run = false;
-}

src/files.c

@@ -0,0 +1,66 @@
+#include "files.h"
+#include <stdio.h>
+#include <gmp.h>
+#include <assert.h>
+
+int inputPrimes(char *file, List *list) {
+	// Assert safeguards
+	assert(file);
+	assert(list);
+
+	FILE *in = fopen(file, "r");
+	if(!in) return 1;
+	mpz_t n;
+	mpz_init(n);
+	while(mpz_inp_raw(n, in))
+		if(addToList(list, n) == 1) return 3;
+
+	mpz_clear(n);
+
+	if(fclose(in)) return 2;
+	return 0;
+}
+
+int outputPrimes(char *file, List *list, size_t startPos) {
+	// Assert safeguards
+	assert(file);
+	assert(list);
+
+	FILE *out = fopen(file, "a");
+	if(!out) return 1;
+
+	printf("Saving primes to `%s'...\n", file);
+	puts("0%");
+	for(size_t i = startPos; i < list->end; ++i) {
+		if(!mpz_out_raw(out, list->list[i])) return 3;
+		if(i == list->end / 4) puts("25%");
+		else if(i == list->end / 2) puts("50%");
+		else if(i == list->end * 3 / 4) puts("75%");
+	}
+	puts("100%");
+
+	if(fclose(out)) return 2;
+	return 0;
+}
+
+int exportPrimes(char *efile, char *dfile, int base) {
+	// Assert safeguards
+	assert(efile);
+	assert(dfile);
+
+	FILE *in = fopen(dfile, "r");
+	FILE *out = fopen(efile, "w");
+	if(!in || !out) return 1;
+
+	printf("Exporting primes to `%s'...\n", efile);
+	mpz_t n;
+	mpz_init(n);
+	while(mpz_inp_raw(n, in)) {
+		if(!mpz_out_str(out, base, n)) return 3;
+		fprintf(out, "\n");
+	}
+
+	if(fclose(in) || fclose(out)) return 2;
+
+	return 0;
+}

src/files.h

@@ -0,0 +1,39 @@
+/**
+ * @file files.h
+ * @author Deathsbreed <deathsbreed@themusicinnoise.net>
+ * @brief Functions to deal with file I/O of primes.
+ * @details Functions that input, output, and export primes from/to files.
+ */
+#pragma once
+#include "list.h"
+
+/**
+ * @brief Load primes from an Indivisible file into a List.
+ * @param file File to input primes from.
+ * @param list List to load primes into.
+ * @returns If 0 then load was successful, if 1 then failed to open,
+ * if 2 failed to close, if 3 failed to allocate new memory to List
+ * (see `addToList()')
+ */
+int inputPrimes(char *file, List *list);
+
+/**
+ * @brief Output primes from a List into an Indivisible file.
+ * @param file File to output primes to.
+ * @param list List to read primes from.
+ * @param startPos The position in the List of primes at which to append
+ * to the file.
+ * @returns If 0 then load was successful, if 1 then failed to open,
+ * if 2 failed to close, if 3 failed when writing.
+ */
+int outputPrimes(char *file, List *list, size_t startPos);
+
+/**
+ * @brief Export primes from a List to a plain text file.
+ * @param efile File to export primes as plain text to.
+ * @param dfile File to read primes from.
+ * @param base The base in which the primes will be written.
+ * @returns If 0 then load was successful, if 1 then failed to open,
+ * if 2 failed to close, if 3 failed when writing.
+ */
+int exportPrimes(char *efile, char *dfile, int base);

src/list.c

@@ -0,0 +1,34 @@
+#include "list.h"
+#include <stdlib.h>
+
+/**
+ * This is the number of elements by which the list expands.
+ */
+#define BLOCK_SIZE 1024
+
+int initList(List *restrict l) {
+	l->list = malloc(sizeof(mpz_t) * BLOCK_SIZE);
+	if(!l->list) return 1;
+	l->size = BLOCK_SIZE;
+	l->end = 0;
+	return 0;
+}
+
+void deInitList(List *restrict l) {
+	for(size_t i = 0; i < l->end; ++i) {
+		mpz_clear(l->list[i]);
+	}
+	free(l->list);
+}
+
+int addToList(List *restrict l, mpz_t n) {
+	if(l->end == l->size) {
+		l->size += BLOCK_SIZE;
+		void *tmp = realloc(l->list, sizeof(mpz_t) * l->size);
+		if(!tmp) return 1;
+		l->list = tmp;
+	}
+	mpz_init(l->list[l->end]);
+	mpz_set(l->list[l->end++], n);
+	return 0;
+}

src/list.h

@@ -0,0 +1,43 @@
+/**
+ * @file list.h
+ * @author Deathsbreed <deathsbreed@themusicinnoise.net>
+ * @brief Code responsible for List management.
+ * @details Code responsible for the definition and management of the
+ * List object.
+ */
+#pragma once
+#include <gmp.h>
+
+/**
+ * @brief An infinitely expanding list type.
+ */
+typedef struct {
+	mpz_t *list; //!< The list of elements
+	size_t size; //!< How many elements are in the list
+	size_t end; //!< The last element of the list (in use)
+} List;
+
+/**
+ * @brief Initialize a List.
+ * @details Initialize the list and its variables, allocating memory
+ * to the pointer array inside.
+ * @param[in] l A pointer to a List type to be initialized.
+ * @returns Returns 0 if successful and 1 if failed.
+ */
+int initList(List *restrict l);
+
+/**
+ * @brief Deinitialize a List.
+ * @details Release all memory that has been allocated to the list.
+ * @param[in] l A pointer to a List type to be deinitialized.
+ */
+void deInitList(List *restrict l);
+
+/**
+ * @brief Adds a new item to a List type.
+ * @details Add item `n' at the end of a List type.
+ * @param[out] l List to which the variable should be appended.
+ * @param[in] n variable to be appended to the list.
+ * @returns Returns 0 if successful and 1 if failed.
+ */
+int addToList(List *restrict l, mpz_t n);

src/main.c

@@ -0,0 +1,282 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <gmp.h>
+#include <omp.h>
+
+#include <sys/stat.h>
+
+#include "list.h"
+#include "files.h"
+
+#define VERSION "v1.0"
+
+static bool run;
+
+void printUsage(char *progName);
+void leave();
+
+int main(int argc, char *argv[]) {
+	// Variables for argument parsing
+	bool f_help = false,
+		 f_version = false,
+		 f_quiet = false;
+	int base = 10;
+	size_t n_prime = 0;
+	char *dfile = NULL;
+	char *efile = NULL;
+
+	// Parse commandline arguments
+	int c;
+	while((c = getopt(argc, argv, "hvqb:f:e:n:")) != -1) {
+		switch(c) {
+			case 'h':
+				f_help = true;
+				break;
+			case 'v':
+				f_version = true;
+				break;
+			case 'q':
+				f_quiet = true;
+				break;
+			case 'b':
+				base = atoi(optarg);
+				if(base < 2 || base > 62) {
+					fprintf(stderr,
+							"Invalid base `%d'. Base must be between 2 and 62.\n",
+							base);
+					return 1;
+				}
+				break;
+			case 'f':
+				dfile = optarg;
+				break;
+			case 'e':
+				efile = optarg;
+				break;
+			case 'n':
+				n_prime = atoi(optarg);
+				if(n_prime <= 2) {
+					fprintf(stderr,
+							"`n' must be larger than 2 (first two primes are 2 and 3).\n");
+					return 1;
+				}
+				break;
+			default:
+				printUsage(argv[0]);
+				return 1;
+		}
+	}
+
+	// Act based on which flags were used
+	if(f_help) {
+		printUsage(argv[0]);
+		puts("\nArguments:");
+		puts(" -h         print this help information");
+		puts(" -v         print version number of program");
+		puts(" -q         quiet mode");
+		puts(" -b <base>  base in which to print primes between 2 and 62 (default 10)");
+		puts(" -f <file>  file in/from which primes are stored and read from in raw format");
+		puts(" -e <file>  export input file to plain text format");
+		puts(" -n <n>     run until the 'n'th prime\n");
+		return 0;
+	} else if(f_version) {
+		printf("Indivisible %s\n", VERSION);
+		return 0;
+	} else if(f_quiet && !dfile) {
+		puts("Error: you cannot run in quiet mode without specifying a data file.");
+		printUsage(argv[0]);
+		return 0;
+	}
+
+	if(efile && !dfile) {
+		puts("Error: you must have a file to export to.");
+		printUsage(argv[0]);
+		return 0;
+	} else if(efile && dfile) {
+		exportPrimes(efile, dfile, base);
+		return 0;
+	}
+
+	if(!omp_get_cancellation()) {
+		puts("Warning: the OpenMP cancellation environment variable (`OMP_CANCELLATION') is not enabled.");
+		char in;
+		while(true) {
+			printf("[e]nable/[c]ontinue/[q]uit? ");
+			scanf("%c", &in);
+			if(in == 'e' || in == 'E') {
+				putenv("OMP_CANCELLATION=true");
+				execv(argv[0], argv);
+			} else if(in == 'c' || in == 'C') {
+				break;
+			} else if(in == 'q' || in == 'Q') {
+				return 0;
+			}
+		}
+	}
+
+	// Quit on ^C by setting `run = false'
+	run = true;
+	signal(SIGINT, leave);
+
+	puts("Use Ctrl+C to exit.");
+
+	bool newFile = true;
+	if(dfile) {
+		struct stat s;
+		if(stat(dfile, &s) == 0) newFile = false;
+	}
+	// Last position added from file
+	size_t startPos = 0;
+
+	int exitCode = 0;
+
+	// Primes we've found
+	List primes;
+	if(initList(&primes) == 1) {
+		fprintf(stderr, "Failed to initialize primes list.\n");
+		exit(1);
+	}
+
+	// The number we're going to be testing for
+	mpz_t num;
+	mpz_init(num);
+
+	// Variable for sqrt of `num'
+	mpz_t numRoot;
+	mpz_init(numRoot);
+	// Index of the prime number above and closest to `numRoot'
+	size_t rootInd = 0;
+
+	if(newFile) {
+		// Add 2, a known prime to this list
+		mpz_set_ui(num, 2);
+		if(addToList(&primes, num) == 1) {
+			fprintf(stderr, "Failed to allocate more memory for list.\n");
+			exitCode = 1;
+			goto releaseMemory;
+		}
+		// Add 3 as well to optimize the algorithm
+		mpz_set_ui(num, 3);
+		if(addToList(&primes, num) == 1) {
+			fprintf(stderr, "Failed to allocate more memory for list.\n");
+			exitCode = 1;
+			goto releaseMemory;
+		}
+		if(!f_quiet) {
+			puts("2\n3");
+		}
+	} else {
+		// Load primes from file
+		int err = inputPrimes(dfile, &primes);
+		startPos = primes.end;
+
+		if(err == 0) {
+			printf("Loaded %zu primes.\n", primes.end);
+		} else {
+			if(err == 1)
+				fprintf(stderr, "Failed to open Indivisible file `%s'.\n", dfile);
+			else if(err == 2)
+				fprintf(stderr, "Failed to close Indivisible file `%s'.\n", dfile);
+			else if(err == 3)
+				fprintf(stderr, "Failed to allocate more memory for list.\n");
+			exitCode = 1;
+			goto releaseMemory;
+		}
+		/**
+		 * I set to `primes.end-1' because primes.end indicates the next new
+		 * element in the list that can be used, which is also equal to the total
+		 * number of elements in the list.
+		 */
+		mpz_set(num, primes.list[primes.end-1]);
+	}
+
+	while(run) {
+		mpz_add_ui(num, num, 2);
+
+		// Calculate the sqrt(num)
+		mpz_sqrt(numRoot, num);
+
+		while(mpz_cmp(primes.list[rootInd], numRoot) <= 0) {
+			if(++rootInd > primes.end) {
+				fprintf(stderr, "Error: `rootInd' surpassed `primes.end'.\n");
+				exitCode = 1;
+				goto releaseMemory;
+			}
+		}
+
+		bool isPrime = true;
+		/**
+		 * Loop through primes we've found until we get to the sqrt of the
+		 * number we're analyzing. Also, skip `2' since we're not testing even
+		 * numbers.
+		 */
+		#pragma omp parallel
+		{
+			#pragma omp for
+			for(size_t i = 1; i < rootInd; ++i) {
+				if(mpz_divisible_p(num, primes.list[i])) {
+					#pragma omp atomic write
+					isPrime = false;
+					#pragma omp cancel for
+				}
+				#pragma omp cancellation point for
+			}
+		}
+
+		if(isPrime) {
+			// `num' is a prime so we add it to the list and print it
+			if(addToList(&primes, num) == 1) {
+				fprintf(stderr, "Failed to allocate more memory for list.\n");
+				exitCode = 1;
+				goto releaseMemory;
+			}
+			if(!f_quiet) {
+				if(!mpz_out_str(stdout, base, num))
+					fprintf(stderr, "Could not print to `stdout'!\n");
+				printf("\n");
+			}
+		}
+
+		if(primes.end == n_prime) break;
+	}
+
+
+	printf("Found %zu primes.\n", primes.end);
+
+	if(dfile) {
+		int err = outputPrimes(dfile, &primes, startPos);
+		if(err == 0) {
+			puts("Successfully saved primes.");
+		} else {
+			if(err == 1)
+				fprintf(stderr, "Failed to open/create file `%s'.\n", dfile);
+			else if(err == 2)
+				fprintf(stderr, "Failed to close file `%s'.\n", dfile);
+			else if(err == 3)
+				fprintf(stderr, "Failed while writing a prime to `%s'.\n", dfile);
+			exitCode = 1;
+			goto releaseMemory;
+		}
+
+	}
+
+releaseMemory:
+	puts("Clearing memory...");
+	// Clear GMP variables
+	mpz_clear(numRoot);
+	mpz_clear(num);
+	// Deinitialize the list
+	deInitList(&primes);
+
+	puts("Exit successful.");
+	return exitCode;
+}
+
+void printUsage(char *progName) {
+	printf("%s [[-f <file> [-e <file> | -q]] [-b <base>] [-n <n>] | [-h] | [-v]]\n", progName);
+}
+
+void leave() { run = false; }