Add more practical examplesHEADmaster

lang.c example automatically redirects to a particular website
version, based on the language prefernces of the user.

style.c cycles through a range of CSS styles.

2 files changed, 200 insertions, 0 deletions

diff --git a/examples/lang.c b/examples/lang.c
new file mode 100644
index 0000000..eb6336e
--- /dev/null
+++ b/examples/lang.c
@@ -0,0 +1,69 @@
+#include <magi.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+static char *scat(const char *a, const char *b)
+{
+    int   alen = a ? strlen(a) : 0;
+    int   blen = b ? strlen(b) : 0;
+    char *res  = malloc(alen + blen + 1);
+    memcpy(res, a, alen);
+    memcpy(res + alen, b, blen);
+    res[alen + blen] = 0;
+    return res;
+}
+
+
+static const char *determ(const char *langprefs)
+{
+    int i;
+    const char *langs[] = { "en", "ru" };
+    const int langslen = 2;
+    const char *min = 0;
+    int minid = 0;
+    for (i = 0; i != langslen; ++i) {
+        const char *res = strstr(langprefs, langs[i]);
+        if (min == 0 || res < min) {
+            min = res;
+            minid = i;
+        }
+    }
+    return langs[minid];
+}
+
+static void response(struct magi_request *req)
+{
+    struct magi_response res;
+    const char *lang = getenv("HTTP_ACCEPT_LANGUAGE");
+    char *a = scat(req->script, req->path);
+    char *b = scat(determ(lang), a);
+    free(a);
+    a = scat("/", b);
+    free(b);
+    b = scat(req->host, a);
+    free(a);
+    a = scat("https://", b);
+    free(b);
+    magi_response_init(&res);
+    magi_response_status(&res, 302, "Moved Temporarily");
+    magi_response_header(&res, "Location", a);
+    free(a);
+    magi_response_send(&res);
+    magi_response_free(&res);
+}
+
+
+int main()
+{
+    struct magi_request request;
+    magi_request_init(&request);
+    if (magi_parse(&request)) {
+        response(&request);
+    } else {
+        magi_error_response(request.error);
+    }
+    magi_request_free(&request);
+    return 0;
+}
diff --git a/examples/style.c b/examples/style.c
new file mode 100644
index 0000000..abaef57
--- /dev/null
+++ b/examples/style.c
@@ -0,0 +1,131 @@
+#include <magi.h>
+#include <dirent.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+static int emptyurl(const char *url)
+{
+    return !url || !*url || (url[0] == '/' && !url[1]);
+}
+
+static int equrl(const char *a, const char *b)
+{
+    if (!a) return !b;
+    if (!b) return 0;
+    while (*a && *b && *a == *b) {
+        ++a;
+        ++b;
+    }
+    return emptyurl(a) && emptyurl(b);
+}
+
+static char *scopy(const char *s)
+{
+    int   len = s ? strlen(s) : 0;
+    char *res  = malloc(len + 1);
+    if (s) memcpy(res, s, len);
+    res[len] = 0;
+    return res;
+}
+
+static char *scat(const char *a, const char *b)
+{
+    int   alen = a ? strlen(a) : 0;
+    int   blen = b ? strlen(b) : 0;
+    char *res  = malloc(alen + blen + 1);
+    memcpy(res, a, alen);
+    memcpy(res + alen, b, blen);
+    res[alen + blen] = 0;
+    return res;
+}
+
+
+static char *nextstyle(const char *curstyle)
+{
+    DIR *d = opendir("/var/web/veresov.pro/public/styles");
+    struct dirent *de;
+    struct dirent *res = readdir(d);
+    while (res->d_name[0] == '.') res = readdir(d);
+    while ((de = readdir(d)) != 0) {
+        if (de->d_name[0] == '.') continue;
+        if (strcmp(de->d_name, curstyle)) {
+            if (de->d_name[0] != '.') res = de;
+            else break;
+        }
+    }
+    closedir(d);
+    return scopy(res->d_name);
+}
+
+static void switchstyle(const char *style, const char *script, const char *r)
+{
+    struct magi_cookie   stl = { 0, 0, 0, 0, 0 };
+    struct magi_response res;
+    magi_response_init(&res);
+    stl.name = scopy("style");
+    stl.data = nextstyle(style);
+    stl.path = scopy(script);
+    magi_response_cookie_complex(&res, &stl);
+    if (r) {
+        magi_response_status(&res, 302, "Moved Temporarily");
+        magi_response_header(&res, "Location", r);
+    }
+    magi_response_send(&res);
+    magi_response_free(&res);
+    free(stl.name);
+    free(stl.data);
+    free(stl.path);
+}
+
+static void getstyle(const char *style, const char *script)
+{
+    char  c;
+    char *p   = scat("/var/web/veresov.pro/public/styles/", style);
+    FILE *f   = fopen(p, "r");
+    struct magi_cookie   stl = { 0, 0, 0, 0, 0 };
+    struct magi_response res;
+    magi_response_init(&res);
+    stl.name = scopy("style");
+    stl.data = scopy(style);
+    stl.path = scopy(script);
+    magi_response_cookie_complex(&res, &stl);
+    magi_response_content_type(&res, "text/css");
+    magi_response_send(&res);
+    magi_response_free(&res);
+    while (fread(&c, 1, 1, f) == 1) {
+        fwrite(&c, 1, 1, stdout);
+    }
+    fclose(f);
+    free(p);
+    free(stl.name);
+    free(stl.data);
+    free(stl.path);
+}
+
+
+static void response(struct magi_request *req)
+{
+    const char *curstyle = magi_request_cookie(req, "style");
+    if (!curstyle) curstyle = "default.css";
+    if (equrl(req->path, "/switch")) {
+        switchstyle(curstyle, req->script, magi_request_param(req, "r"));
+    } else if (equrl(req->path, "/style.css")) {
+        getstyle(curstyle, req->script);
+    }
+}
+
+
+int main()
+{
+    struct magi_request request;
+    magi_request_init(&request);
+    if (magi_parse(&request)) {
+        response(&request);
+    } else {
+        magi_error_response(request.error);
+    }
+    magi_request_free(&request);
+    return 0;
+}