Add c demo

c/demo/assembly/hello.c

@@ -0,0 +1,6 @@
+#include<stdio.h>
+int main()
+{
+	printf("Hello World!");
+	return 0;
+}

c/demo/binary.c

@@ -0,0 +1,149 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <errno.h>
+#include <string.h>
+
+#define SL(str)    (str), (sizeof(str)-1)
+
+typedef struct _binary {
+    FILE *fp;
+    int pos;
+} Binary;
+
+size_t file_size(FILE *fp) {
+    size_t size;
+    fseek(fp, 0L, SEEK_END);
+    size = ftell(fp);
+    fseek(fp, 0L, SEEK_SET);
+    return size;
+}
+
+size_t file_write (FILE *fp, const void *data, size_t size) {
+    return fwrite(data, sizeof(char), size, fp);
+}
+
+int binary_open(Binary *bin, const char *filename, const char *modes) {
+    bin->fp = fopen(filename, modes);
+    bin->pos = 0;
+    if (bin->fp == NULL) {
+        printf("open fail errno = %d reason = %s \n", errno, strerror(errno));
+    }
+    return bin->fp ? 1 : 0;
+}
+
+int binary_close(Binary *bin) {
+    bin->pos = 0;
+    return fclose(bin->fp);
+}
+
+int binary_setpos(Binary *bin, int pos) {
+    int ret = fseek(bin->fp, pos, SEEK_SET);
+    if (!ret) { // !0
+        bin->pos = pos;
+    }
+    return ret;
+}
+
+char *binary_read(Binary *bin, int length) {
+    char *result = calloc(length + 1, sizeof (char));
+    int i = 0;
+    int c;
+    while (i < length && (c = fgetc(bin->fp)) != EOF) {
+        result[i] = c;
+        i++;
+    }
+    if (i != length) {
+        free(result);
+        binary_setpos(bin, bin->pos);
+        return NULL;
+    }
+    bin->pos += i;
+    return result;
+}
+
+int binary_skip(Binary *bin, int length) {
+    if (length <= 0) {
+        int i = 0;
+        int c;
+        while ((c = fgetc(bin->fp)) != EOF) {
+            i++;
+            if (c == '\0') {
+                break;
+            }
+        }
+        bin->pos += i;
+        return 0;
+    }
+    int ret = fseek(bin->fp, length, SEEK_CUR);
+    if (!ret) { // !0
+        bin->pos += length;
+    }
+    return ret;
+}
+
+int binary_strpos(Binary *bin, const char *neele, size_t len) {
+    int i = 0;
+    int found = 0;
+    int c;
+    while (found < len && (c = fgetc(bin->fp)) != EOF) {
+        if (c == neele[found]) {
+            found++;
+        } else {
+            found = 0;
+        }
+        i++;
+    }
+
+    binary_setpos(bin, bin->pos);
+
+    return found == len ? (bin->pos + i - len) : -1;
+}
+
+char *binary_readString(Binary *bin) {
+    int length = 512;
+    char *result = calloc(length, sizeof (char));
+    int i = 0;
+    int c;
+    while ((c = fgetc(bin->fp)) != EOF) {
+        if (i >= length) {
+            char *ptr = NULL;
+            length *= 2;
+            ptr = realloc(result, length);
+            if (!ptr) {
+                return result;
+            }
+            result = ptr;
+        }
+        result[i] = c;
+        i++;
+        if (c == '\0') {
+            break;
+        }
+    }
+    bin->pos += i;
+
+    return result;
+}
+
+uint32_t binary_readUint32(Binary *bin) {
+    uint32_t value = 0;
+    //bytes[0] + bytes[1]*256 + + bytes[2]*65536 + bytes[3]*16777216;
+    int length = 4;
+    int i = 0;
+    int c;
+    while (i < length && (c = fgetc(bin->fp)) != EOF) {
+        value += (unsigned char) c << 8 * i;
+        i++;
+    }
+    bin->pos += i;
+    return value;
+}
+
+int binary_pos(Binary *bin) {
+    return bin->pos;
+}
+
+int binary_eof(Binary *bin) {
+    return feof(bin->fp);
+}