feat(io): Initial implementation

Implement `io_readline` and `io_fill` operations and introduce IO API
extension to the library.

Author: SpacingBat3

CMakeLists.txt

@@ -50,7 +50,7 @@ message(VERBOSE "YAVL: C symbol namespace: ${YAVL_C_NAMESPACE}")
 
 ## 2. List of auto-generated headers
 set("${PROJECT_NAME}_GEN_HEADERS"
-  "vec.h")
+  "vec.h" "io.h")
 
 # Target list
 # ===========
@@ -126,7 +126,7 @@ endif()
 
 # Header generation and inclusion to API
 # ======================================
-foreach(header "${${PROJECT_NAME}_GEN_HEADERS}")
+foreach(header IN LISTS "${PROJECT_NAME}_GEN_HEADERS")
   configure_file(
     "${CMAKE_CURRENT_SOURCE_DIR}/template/include/YAVL/${header}.in"
     "${${PROJECT_NAME}_GEN_HEADERS_OUTPUT_DIRECTORY}/YAVL/${header}"

src/io.c

@@ -0,0 +1,60 @@
+/*
+ * io.c - I/O API based on vector for dynamic allocation
+ *
+ * SPDX-License: GPL-3.0-or-later
+ *
+ * Copyright (C) 2026 Dawid Papiewski
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+ * You should have received a copy of the GNU General Public License along with this
+ * program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#include <stdio.h>
+#include <YAVL/vec.h>
+#include <YAVL/io.h>
+#include "namespace.h"
+
+NS(vec_res_t) NS(io_fromstream)(NS(vec_t) *const vec, FILE *const stream) {
+    if(vec->allign != sizeof(char)) return NS_UPPER(VEC_RES_FAIL);
+    for(
+        size_t cr=1;
+        cr!=0;
+        cr=fread(
+            /*__ptr=*/ vec->data+(vec->len*vec->allign),
+            /*__size=*/ vec->allign,
+            /*__n=*/ vec->reservd-vec->len,
+            /*__stream=*/ stream
+        )
+    ) {
+        vec->len += cr;
+        // Autoscale
+        NS(vec_res_t) res;
+        if(vec->reservd <= vec->len) res = NS(vec_scale)(vec, vec->reservd*2);
+        if(res != NS_UPPER(VEC_RES_OK)) return res;
+    }
+    NS(vec_fit)(vec);
+    return NS_UPPER(VEC_RES_OK);
+}
+
+NS(vec_res_t) NS(io_readline)(NS(vec_t) *const vec, FILE *const stream) {
+    if(vec->allign != sizeof(char)) return NS_UPPER(VEC_RES_FAIL);
+    for(
+        int ch=0;
+        ch!='\n'||ch==EOF;
+        ch=getc(stream)
+    ) {
+        char c = ch; NS(vec_res_t) res;
+        if((res = NS(vec_push)(vec,&c,1)) != NS_UPPER(VEC_RES_OK))
+            return res;
+    }
+    const char trail[] = "\n";
+    NS(vec_push)(vec, trail, sizeof(trail)/sizeof(trail[0]));
+    return NS(vec_fit)(vec);
+}

src/vec.c

@@ -1,4 +1,6 @@
 /*
+ * vec.c - Core vector API
+ *
  * SPDX-License: GPL-3.0-or-later
  *
  * Copyright (C) 2026 Dawid Papiewski

template/include/YAVL/io.h.in

@@ -0,0 +1,50 @@
+/** @file
+ *
+ * I/O API extension
+ *
+ * SPDX-License: GPL-3.0-or-later
+ *
+ * @author Dawid Papiewski
+ * @copyright (C) 2026 Dawid Papiewski
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+ * You should have received a copy of the GNU General Public License along with this
+ * program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#pragma once
+#ifndef @YAVL_C_NAMESPACE_UPPER_@IO_H
+#define @YAVL_C_NAMESPACE_UPPER_@IO_H
+#pragma clang final(@YAVL_C_NAMESPACE_UPPER_@IO_H)
+#include "vec.h"
+/** @defgroup IO I/O API
+ *
+ * @brief Stream read and buffering API,
+ * made for parsers in mind.
+ *
+ * @{
+ */
+
+/**
+ * Read from stream until finding '\n'
+ *
+ * @param vec Vector to push buffer into.
+ * @param stream Stream to read line from.
+ */
+@YAVL_C_NAMESPACE_@vec_res_t @YAVL_C_NAMESPACE_@io_readline(@YAVL_C_NAMESPACE_@vec_t *const vec, FILE *const stream);
+/**
+ * Buffer entire stream into vector.
+ *
+ * @param vec Vector to buffer stream into.
+ * @param stream Stream to read data from.
+ */
+@YAVL_C_NAMESPACE_@vec_res_t @YAVL_C_NAMESPACE_@io_fill(@YAVL_C_NAMESPACE_@vec_t *const vec, FILE *const stream);
+
+/** @} */ // IO
+#endif

template/include/YAVL/vec.h.in

@@ -19,6 +19,7 @@
  * program.  If not, see <https://www.gnu.org/licenses/>.
  *
  */
+#pragma once
 #ifndef @YAVL_C_NAMESPACE_UPPER_@VEC_H
 #define @YAVL_C_NAMESPACE_UPPER_@VEC_H
 #pragma clang final(@YAVL_C_NAMESPACE_UPPER_@VEC_H)