ppdfviewer, basic, bits and string view

c/bits/bit1/main.c

@@ -0,0 +1,25 @@
+#include <stdio.h>
+
+int main(void) {
+
+    unsigned char flags = 0b0000010;
+
+    unsigned char FLAG_A = 1u << 0;
+    unsigned char FLAG_B = 1u << 1;
+
+    printf("El FLAG_A es: %08b\n", FLAG_A);
+    printf("El FLAG_B es: %08b\n", FLAG_B);
+
+    // encender ambos.
+    flags = (FLAG_A | FLAG_B);
+
+    if (flags & (FLAG_A)) {
+        printf("El flag A esta encendido\n");
+    }
+
+    if (flags & (FLAG_B)) {
+        printf("El flag B esta encendido\n");
+    }
+
+    return 0;
+}

c/files/files3/main.c

@@ -1,8 +1,18 @@
+#include <SDL2/SDL.h>
+#include <SDL2/SDL_error.h>
+#include <SDL2/SDL_events.h>
+#include <SDL2/SDL_log.h>
+#include <SDL2/SDL_render.h>
+#include <SDL2/SDL_video.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
+void render_image(SDL_Renderer *ref_renderer, unsigned char *data,
+                  unsigned long w, unsigned long h);
+
 int main(int argc, char *argv[]) {
     if (argc < 2) {
         fprintf(stderr, "Argumentos invalidos\n");
@@ -79,7 +89,78 @@ int main(int argc, char *argv[]) {
         fclose(pfile);
     }
 
+    if (SDL_Init(SDL_INIT_VIDEO) < 0) {
+        perror("SLD_Init");
+        free(data);
+        fclose(pfile);
+        return 1;
+    }
+
+    SDL_Window *window =
+        SDL_CreateWindow("Visor de imagenes", SDL_WINDOWPOS_CENTERED,
+                         SDL_WINDOWPOS_CENTERED, w, h, SDL_WINDOW_SHOWN);
+
+    if (window == NULL) {
+        SDL_Log("SLD_WINDOW: %s", SDL_GetError());
+        SDL_Quit();
+        free(data);
+        fclose(pfile);
+        return 1;
+    }
+
+    SDL_Renderer *renderer = SDL_CreateRenderer(
+        window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
+
+    if (!renderer) {
+        SDL_Log("No se pudo crear el renderizador: %s", SDL_GetError());
+        SDL_DestroyWindow(window);
+        SDL_Quit();
+        free(data);
+        fclose(pfile);
+        return 1;
+    }
+
+    bool running = true;
+    SDL_Event ev;
+    while (running) {
+        while (SDL_PollEvent(&ev)) {
+            if (ev.type == SDL_QUIT) {
+                running = 0; // Si hacen clic en la "X", salimos
+            }
+            if (ev.type == SDL_KEYDOWN) {
+                // Si presionan Escape, salimos
+                if (ev.key.keysym.sym == SDLK_ESCAPE) {
+                    running = 0;
+                }
+            }
+        }
+
+        SDL_RenderClear(renderer);
+        render_image(renderer, data, w, h);
+        SDL_RenderPresent(renderer);
+    }
+
+    SDL_DestroyRenderer(renderer);
+    SDL_DestroyWindow(window);
+    SDL_Quit();
+
     free(data);
     fclose(pfile);
     return 0;
 }
+
+void render_image(SDL_Renderer *ref_renderer, unsigned char *rdata,
+                  unsigned long int w, unsigned long h) {
+
+    unsigned long offset = 0;
+    for (unsigned long cury = 0; cury < h; cury++) {
+        for (unsigned long curx = 0; curx < w; curx++) {
+            uint8_t r = *(rdata + offset++);
+            uint8_t g = *(rdata + offset++);
+            uint8_t b = *(rdata + offset++);
+
+            SDL_SetRenderDrawColor(ref_renderer, r, g, b, 255);
+            SDL_RenderDrawPoint(ref_renderer, curx, cury);
+        }
+    }
+}

c/stringview/main.c

@@ -0,0 +1,13 @@
+#include "stringv.h"
+#include <stdio.h>
+int main(void) {
+    StringView s1 = sv_from_cstr("Hola mundo con string view");
+    StringView s2 = sv_from_cstr("😊");
+    StringView last = sv_right(&s1, 4);
+
+    printf("El string view contiene: %s\n", s2.text);
+    printf("El length es: %zu\n", s2.lenght);
+
+    printf("last tiene:%.*s\n", (int)last.lenght, last.text);
+    return 0;
+}

c/stringview/stringv.c

@@ -0,0 +1,60 @@
+#include "stringv.h"
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
+
+/*
+ * @brief Create a string view from a const char* and  set their lenght
+ *
+ * @details This string view provides a view of a string. It does not allocate
+ * memory, therefore, it lives only while the source is alive. The
+ * lenght is a bytes number of the string. It does not represents the number of
+ * characters.
+ *
+ * @param str pointer from the original string. It can be NULL.
+ *
+ * @return a StringView with the view of original string with corresponding
+ * lenght.
+ */
+
+#define STRING_VIEW_NULL (StringView){.text = NULL, .lenght = 0}
+
+StringView sv_from_cstr(const char *str) {
+    if (str == NULL) {
+        return STRING_VIEW_NULL;
+    }
+    return (StringView){.text = (char *)str, .lenght = strlen(str)};
+}
+
+StringView sv_left(const StringView *sv, size_t l) {
+    if (sv == NULL) {
+        perror("sv_left: pointer is NULL\n");
+        return STRING_VIEW_NULL;
+    }
+    if (sv->text == NULL) {
+        perror("sv_left: text pointer is NULL\n");
+        return STRING_VIEW_NULL;
+    }
+    if (sv->lenght < l) {
+        perror("sv_left: text length is less than specified length\n");
+        return STRING_VIEW_NULL;
+    }
+    return (StringView){.text = sv->text, .lenght = l};
+}
+
+StringView sv_right(const StringView *sv, size_t r) {
+    if (sv == NULL) {
+        perror("sv_right: pointer is NULL\n");
+        return STRING_VIEW_NULL;
+    }
+    if (sv->text == NULL) {
+        perror("sv_right: text pointer is NULL\n");
+        return STRING_VIEW_NULL;
+    }
+    if (sv->lenght < r) {
+        perror("sv_right: text length is less than specified length\n");
+        return STRING_VIEW_NULL;
+    }
+    size_t nlength = sv->lenght - r;
+    return (StringView){.text = sv->text + nlength, .lenght = r};
+}

c/stringview/stringv.h

@@ -0,0 +1,14 @@
+#ifndef STRING_VIEW_H
+#define STRING_VIEW_H
+
+#include <stddef.h>
+
+typedef struct StringView {
+    char *text;
+    size_t lenght;
+} StringView;
+
+StringView sv_from_cstr(const char *);
+StringView sv_left(const StringView *sv, size_t l);
+StringView sv_right(const StringView *sv, size_t l);
+#endif