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-rw-r--r--userspace/Makefile4
-rw-r--r--userspace/brainfuck.c133
-rw-r--r--userspace/syscalls.c85
-rw-r--r--userspace/test.c81
4 files changed, 221 insertions, 82 deletions
diff --git a/userspace/Makefile b/userspace/Makefile
index 2a286da..bd1e6ec 100644
--- a/userspace/Makefile
+++ b/userspace/Makefile
@@ -8,7 +8,7 @@ LDFLAGS=-L/home/miguel/temp/fool-os-stuff/newlib-build-clean/i686-elf/newlib/ \
-L/home/miguel/temp/fool-os-stuff/newlib-build-clean/i686-elf/libgloss/libnosys/ \
-lnosys
-all: test.o crt0.o
- ${CC} -T linker.ld ${LDFLAGS} test.o -Wl,--oformat,binary -o userprog
+all: brainfuck.o crt0.o
+ ${CC} -T linker.ld ${LDFLAGS} brainfuck.o -Wl,--oformat,binary -o userprog
clean:
-rm *.o *.out userprog
diff --git a/userspace/brainfuck.c b/userspace/brainfuck.c
new file mode 100644
index 0000000..03ce4f5
--- /dev/null
+++ b/userspace/brainfuck.c
@@ -0,0 +1,133 @@
+// taken from: http://it-ride.blogspot.com/2009/11/brainfuck-interpreter.html
+
+/* comment
+ * TODO
+ * You have a bug. You don't check for EOF while looking for square brackets.
+ */
+
+/*
+
+ A brainfuck intepreter written in C, complete with error checking so you
+ don't hurt yourself while, uh, brainfucking. Nothing really special about
+ the implementation and it is probably very poor performance-wise.
+
+ Author: Felix Oghină
+ License: (brain)fuck licenses!
+
+*/
+
+// ADDED BY FOOLOS : foolos syscalls!
+#include "syscalls.c"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+// by brainfuck standards (doesn't that sound funny?), the data pointer has
+// 30,000 bytes at its disposal, but I hate hard-coding such stuff.
+#define DATA_SIZE 30000
+
+void usage() {
+ puts(
+ "Usage: brainfuck FILE\n"
+ "If FILE is ommited or is '-', standard input is read"
+ );
+}
+
+int main(int argc, char **argv) {
+
+ // ADDED BY FOOLOS: we will show usage anyway
+ usage();
+
+ // used by the bf program
+ unsigned char *dataptr = malloc(sizeof(char) * DATA_SIZE);
+ // position of the data pointer
+ unsigned int datapos = 0;
+ // input file
+ FILE *input;
+ // level - deepness of brackets
+ // i - uh, you need explanation for this one?
+ unsigned int level, i;
+ // we will read chars from the input into r
+ unsigned char r;
+
+ // determine input
+ if (argc == 2) {
+ if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-h") == 0) {
+ usage();
+ return EXIT_SUCCESS;
+ }
+ else {
+ input = fopen(argv[1], "r");
+ if (input == NULL) {
+ puts("Error opening input file");
+ return EXIT_FAILURE;
+ }
+ }
+ }
+ else {
+ usage();
+ return EXIT_FAILURE;
+ }
+
+ // zero the data pointer
+ for (i=0; i < DATA_SIZE; i++) {
+ dataptr[i] = 0;
+ }
+
+ // start interpreting
+ rewind(input);
+ while (!feof(input)) {
+ r = (unsigned char) fgetc(input);
+ switch(r) {
+ case '>':
+ if (datapos < DATA_SIZE - 1) datapos++;
+ else {
+ puts("brainfuck error: pointer overflow");
+ return EXIT_FAILURE;
+ }
+ break;
+ case '<':
+ if (datapos > 0) datapos--;
+ else {
+ puts("brainfuck error: pointer underflow");
+ return EXIT_FAILURE;
+ }
+ break;
+ case '+':
+ dataptr[datapos]++;
+ break;
+ case '-':
+ dataptr[datapos]--;
+ break;
+ case '.':
+ putchar(dataptr[datapos]);
+ break;
+ case ',':
+ dataptr[datapos] = getchar();
+ break;
+ case '[':
+ if (dataptr[datapos] == 0) {
+ level = 1;
+ while (level != 0) {
+ r = (unsigned char) fgetc(input);
+ if (r == '[') level ++;
+ else if (r == ']') level --;
+ }
+ }
+ break;
+ case ']':
+ if (dataptr[datapos] != 0) {
+ level = 1;
+ while (level != 0) {
+ fseek(input, -2, SEEK_CUR);
+ r = (unsigned char) fgetc(input);
+ if (r == ']') level ++;
+ else if (r == '[') level --;
+ }
+ }
+ break;
+ }
+ }
+ return EXIT_SUCCESS;
+}
diff --git a/userspace/syscalls.c b/userspace/syscalls.c
new file mode 100644
index 0000000..6547879
--- /dev/null
+++ b/userspace/syscalls.c
@@ -0,0 +1,85 @@
+
+//printf needs following syscalls: sbrk write close fstat isatty lseek read
+//
+
+#include <sys/stat.h>
+
+int close(int file)
+{
+ return -1;
+}
+
+int fstat(int file, struct stat *st)
+{
+ st->st_mode = S_IFCHR;
+ return 0;
+}
+
+int isatty(int file) {
+ return 1;
+}
+
+int lseek(int file, int ptr, int dir) {
+ return 0;
+}
+
+int read(int file, char *ptr, int len) {
+ return 0;
+}
+ int open(const char *name, int flags, int mode) {
+ return -1;
+ }
+
+
+int write(int file, char *ptr, int len)
+{
+
+ int todo;
+ for (todo = 0; todo < len; todo++)
+ {
+
+ char byte=(*ptr++);
+ int byt=byte;
+
+ int ebx; // will hold return value;
+ // system call
+ asm("pusha");
+ asm("mov $61,%eax"); // select syscall)
+
+ asm("mov %0,%%edx"::"m"(byt));
+ //asm("mov $88,%edx");
+
+ asm("int $0x80"); // actual syscall ! interrupt
+ asm("mov %%ebx, %0": "=b" (ebx));
+ asm("popa");
+ //
+
+ }
+ return len;
+}
+
+caddr_t sbrk(int incr)
+{
+
+// extern char _end; /* Defined by the linker */
+ char _end;
+ static char *heap_end;
+ char *prev_heap_end;
+
+ if (heap_end == 0) {
+ heap_end = &_end;
+ }
+ prev_heap_end = heap_end;
+ /*
+ if (heap_end + incr > stack_ptr) {
+ write (1, "Heap and stack collision\n", 25);
+ abort ();
+ }
+ */
+
+ heap_end += incr;
+ return (caddr_t) prev_heap_end;
+}
+
+//
+
diff --git a/userspace/test.c b/userspace/test.c
index bdc6da0..12226d3 100644
--- a/userspace/test.c
+++ b/userspace/test.c
@@ -1,86 +1,7 @@
#include <stdlib.h>
#include <stdio.h>
-
-//printf needs following syscalls: sbrk write close fstat isatty lseek read
-//
-
-#include <sys/stat.h>
-
-int close(int file)
-{
- return -1;
-}
-
-int fstat(int file, struct stat *st)
-{
- st->st_mode = S_IFCHR;
- return 0;
-}
-
-int isatty(int file) {
- return 1;
-}
-
-int lseek(int file, int ptr, int dir) {
- return 0;
-}
-
-int read(int file, char *ptr, int len) {
- return 0;
-}
-
-int write(int file, char *ptr, int len)
-{
-
- int todo;
- for (todo = 0; todo < len; todo++)
- {
-
- char byte=(*ptr++);
- int byt=byte;
-
- int ebx; // will hold return value;
- // system call
- asm("pusha");
- asm("mov $61,%eax"); // select syscall)
-
- asm("mov %0,%%edx"::"m"(byt));
- //asm("mov $88,%edx");
-
- asm("int $0x80"); // actual syscall ! interrupt
- asm("mov %%ebx, %0": "=b" (ebx));
- asm("popa");
- //
-
- }
- return len;
-}
-
-caddr_t sbrk(int incr)
-{
-
-// extern char _end; /* Defined by the linker */
- char _end;
- static char *heap_end;
- char *prev_heap_end;
-
- if (heap_end == 0) {
- heap_end = &_end;
- }
- prev_heap_end = heap_end;
- /*
- if (heap_end + incr > stack_ptr) {
- write (1, "Heap and stack collision\n", 25);
- abort ();
- }
- */
-
- heap_end += incr;
- return (caddr_t) prev_heap_end;
-}
-
-//
+#include "syscalls.h>
int main()
{
generated by cgit v1.2.3 (git 2.25.1) at 2025-11-09 07:42:21 +0000