c-programming

commit da2f30b9ab22f5277a82998c1c0247d058a2fcb1
parent 8fa467e6be59b877c3d939c0fcc5892498a62970
Author: Andrew Laack <andrew@laack.co>
Date:   Tue, 11 Nov 2025 06:34:59 -0600

Started working on csv reader

Diffstat:
A
ml/count-columns.c
 | 
36
++++++++++++++++++++++++++++++++++++
A
ml/count-columns.h
 | 
4
++++
A
ml/dynamic-array.c
 | 
109
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
A
ml/dynamic-array.h
 | 
10
++++++++++
A
ml/read-csv.c
 | 
37
+++++++++++++++++++++++++++++++++++++

5 files changed, 196 insertions(+), 0 deletions(-)
diff --git a/ml/count-columns.c b/ml/count-columns.c
@@ -0,0 +1,36 @@
+#include <stdio.h>
+
+int countColumns(char* filename){
+    FILE* fp = fopen(filename, "r");
+    char buffer[1024];
+    int columns = 0;
+    int done = -1;
+    int currentChars = 0;
+    while(fgets(buffer, 1024, fp) && done == -1){
+        for(int i = 0; i < 1024 ; ++i){
+            if(buffer[i] == ','){
+                columns += 1;
+                currentChars = 0;
+            }
+            else if(buffer[i] == '\n' || buffer[i] == 0 || buffer[i] == EOF){
+                done = 0;
+                break;
+            }
+            else{
+                currentChars += 1;
+            }
+        }
+    }
+    if (currentChars > 0){
+        columns += 1;
+    }
+    return columns;
+}
+
+//int main(int argc, char** argv){
+//
+//    int columnCount = countColumns(argv[1]);
+//    printf("%d\n\n", columnCount);
+//
+//    return 0;
+//}
diff --git a/ml/count-columns.h b/ml/count-columns.h
@@ -0,0 +1,4 @@
+#ifndef COUNT_COLUMNS_H
+#define COUNT_COLUMNS_H
+int countColumns(char* filename);
+#endif
diff --git a/ml/dynamic-array.c b/ml/dynamic-array.c
@@ -0,0 +1,109 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+typedef struct{
+    char* data;
+    int size;
+    int capacity;
+}DynamicArray;
+
+DynamicArray* makeArr(char* data, int size){
+    int capacity = size * 2;
+    DynamicArray* result = malloc(sizeof(DynamicArray));
+
+    char* localData = malloc(capacity * sizeof(char));
+    for(int i = 0; i < size; ++i){
+        localData[i] = data[i];
+    }
+
+    result->data = localData;
+    result->size = size;
+    result->capacity = capacity;
+    return result;
+}
+
+
+void extendArr(DynamicArray* arr){
+    int resultingCap = arr->capacity * 2;
+    if(resultingCap == 0){
+        resultingCap = 1;
+    }
+    char* newArr = malloc(resultingCap * sizeof(char));
+    for(int i = 0; i < arr->size; ++i){
+        newArr[i] = arr->data[i];
+    }
+    free(arr->data);
+    arr->data = newArr;
+    arr->capacity = resultingCap;
+}
+
+void printArr(DynamicArray* arr){
+    for(int i = 0 ; i < arr->size; ++i){
+        printf("%c", arr->data[i]);
+    }
+}
+
+void arrAppend(DynamicArray* arr, char element){
+    if(arr->capacity > arr->size){
+        arr->data[arr->size] = element;
+        arr->size += 1;
+    }
+    else{
+        extendArr(arr);
+        arrAppend(arr, element);
+    }
+}
+
+void arrCompress(DynamicArray* arr){
+    int resultingCap = arr->size;
+    char* newData = malloc(sizeof(char) * resultingCap);
+    for(int i = 0; i < arr->size; ++i){
+        newData[i] = arr->data[i];
+    }
+    free(arr->data);
+    arr->data = newData;
+    arr->capacity = resultingCap;
+}
+
+
+void arrPop(DynamicArray* arr){
+
+    if(arr->size == 0){
+        return;
+    }
+    // if it is at least half full, no need to resize
+    if(arr->size > arr->capacity/2){
+        arr->size -= 1;
+    }
+    else{
+        arrCompress(arr);
+        arrPop(arr);
+    }
+}
+
+//int main(){
+//
+//    for(int i = 0; i < 10; ++i){
+//
+//
+//        int size = 0;
+//        int data [size];
+//
+//        DynamicArray* arr = makeArr(data, size);
+//
+//        for(int i = 0 ; i < 1000000; ++i){
+//            arrAppend(arr,i);
+//        }
+//        char* before = "Size after appending:";
+//        printf("%30s %10d\n", before, arr->size);
+//        //printArr(arr);
+//        for(int i = 0 ; i < 1000000; ++i){
+//            arrPop(arr);
+//        }
+//        char* after = "Size after popping:";
+//        printf("%30s %10d\n", after, arr->size);
+//        //printArr(arr);
+//        free(arr->data);
+//        free(arr);
+//    }
+//}
diff --git a/ml/dynamic-array.h b/ml/dynamic-array.h
@@ -0,0 +1,10 @@
+typedef struct{
+    char* data;
+    int size;
+    int capacity;
+}DynamicArray;
+DynamicArray* makeArr(char* data, int size);
+void extendArr(DynamicArray* arr);
+void printArr(DynamicArray* arr);
+void arrAppend(DynamicArray* arr, char element);
+void arrPop(DynamicArray* arr);
diff --git a/ml/read-csv.c b/ml/read-csv.c
@@ -0,0 +1,37 @@
+#include <stdio.h>
+#include "count-columns.h"
+#include "dynamic-array.h"
+#include <stdlib.h>
+
+int main(int argc, char ** argv){
+    
+    char* filename = argv[1];
+    int columns = countColumns(filename);
+    printf("columns: %d\n", columns);
+
+    int size = 0;
+    char data [size];
+    FILE* fp = fopen(filename, "r");
+    DynamicArray* first = makeArr(data,size);
+    DynamicArray* second = makeArr(data,size);
+
+    char c;
+    while ((c = getc(fp)) != ','){
+        arrAppend(first, c);
+    }
+
+    while ((c = getc(fp)) != '\n'){
+        arrAppend(second, c);
+    }
+
+    printArr(first);
+    printf("\n");
+    printArr(second);
+    printf("\n");
+
+    // todo: cleanup allocations
+
+    fclose(fp);
+
+    return 0;
+}