WIP untested Impl. html generation from templates

Makefile

@@ -17,7 +17,8 @@ HEADERS = \
 	src/signal_handling.h \
 	src/constants.h \
 	src/http.h \
-	src/config.h
+	src/config.h \
+	src/http_template.h
 
 SOURCES = \
 		src/main.c \
@@ -28,6 +29,7 @@ SOURCES = \
 		src/globals.c \
 		src/http.c \
 		src/config.c \
+		src/http_template.c \
 		third_party/SimpleArchiver/src/helpers.c \
 		third_party/SimpleArchiver/src/data_structures/linked_list.c \
 		third_party/SimpleArchiver/src/data_structures/hash_map.c \

src/http_template.c

@@ -0,0 +1,277 @@
+// ISC License
+// 
+// Copyright (c) 2024 Stephen Seo
+// 
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+#include "http_template.h"
+
+// Standard library includes.
+#include <string.h>
+#include <stdlib.h>
+
+// Third party includes.
+#include <SimpleArchiver/src/data_structures/linked_list.h>
+#include <SimpleArchiver/src/helpers.h>
+
+typedef struct C_SIMPLE_HTTP_INTERNAL_Template_Node {
+  char *html;
+  size_t html_size;
+  union {
+    size_t orig_end_idx;
+    size_t html_capacity;
+  };
+  SDArchiverLinkedList *forced_next;
+} C_SIMPLE_HTTP_INTERNAL_Template_Node;
+
+void c_simple_http_internal_free_template_node(void *data) {
+  C_SIMPLE_HTTP_INTERNAL_Template_Node *node = data;
+  if (node) {
+    if (node->html) {
+      free(node->html);
+    }
+    if (node->forced_next) {
+      simple_archiver_list_free(&node->forced_next);
+    }
+    free(node);
+  }
+}
+
+void c_simple_http_internal_cleanup_template_node(
+    C_SIMPLE_HTTP_INTERNAL_Template_Node **node) {
+  if (node && *node) {
+    c_simple_http_internal_free_template_node(*node);
+    *node = NULL;
+  }
+}
+
+int c_simple_http_internal_get_final_size_fn(void *data, void *ud) {
+  size_t *final_size = ud;
+  C_SIMPLE_HTTP_INTERNAL_Template_Node *node = data;
+  *final_size += node->html_size;
+  return 0;
+}
+
+int c_simple_http_internal_fill_buf_fn(void *data, void *ud) {
+  C_SIMPLE_HTTP_INTERNAL_Template_Node *node = data;
+  C_SIMPLE_HTTP_INTERNAL_Template_Node *to_fill = ud;
+  if (to_fill->html_capacity < to_fill->html_size + node->html_size) {
+    return 1;
+  }
+  memcpy(
+    to_fill->html + to_fill->html_size,
+    node->html,
+    node->html_size);
+  to_fill->html_size += node->html_size;
+  return 0;
+}
+
+char *c_simple_http_path_to_generated(
+    const char *path,
+    const C_SIMPLE_HTTP_HTTPTemplates *templates) {
+  C_SIMPLE_HTTP_ParsedConfig *wrapped_hash_map =
+    simple_archiver_hash_map_get(templates->hash_map, path, strlen(path) + 1);
+  if (!wrapped_hash_map) {
+    return NULL;
+  }
+  __attribute__((cleanup(simple_archiver_helper_cleanup_c_string)))
+  char *html_buf = NULL;
+  size_t html_buf_size = 0;
+  const char *html_filename =
+    simple_archiver_hash_map_get(wrapped_hash_map->hash_map, "HTML_FILE", 10);
+  if (html_filename) {
+    __attribute__((cleanup(simple_archiver_helper_cleanup_FILE)))
+    FILE *f = fopen(html_filename, "r");
+    if (!f) {
+      return NULL;
+    }
+    if (fseek(f, 0, SEEK_END) != 0) {
+      return NULL;
+    }
+    long html_file_size = ftell(f);
+    if (html_file_size <= 0) {
+      return NULL;
+    }
+    if (fseek(f, 0, SEEK_SET) != 0) {
+      return NULL;
+    }
+    html_buf = malloc(html_file_size + 1);
+    size_t ret = fread(html_buf, 1, html_file_size, f);
+    if (ret != (size_t)html_file_size) {
+      return NULL;
+    }
+    html_buf[html_file_size] = 0;
+    html_buf_size = html_file_size;
+  } else {
+    char *stored_html =
+      simple_archiver_hash_map_get(wrapped_hash_map->hash_map, "HTML", 5);
+    if (!stored_html) {
+      return NULL;
+    }
+    size_t stored_html_size = strlen(stored_html) + 1;
+    html_buf = malloc(stored_html_size);
+    memcpy(html_buf, stored_html, stored_html_size);
+    html_buf_size = stored_html_size;
+  }
+
+  // At this point, html_buf contains the raw HTML as a C-string.
+  __attribute__((cleanup(simple_archiver_list_free)))
+  SDArchiverLinkedList *template_html_list = simple_archiver_list_init();
+
+  size_t idx = 0;
+  size_t last_template_idx = 0;
+
+  __attribute__((cleanup(c_simple_http_internal_cleanup_template_node)))
+  C_SIMPLE_HTTP_INTERNAL_Template_Node *template_node = NULL;
+
+  size_t delimeter_count = 0;
+
+  // xxxx xxx0 - Initial state, no delimeter reached.
+  // xxxx xxx1 - Three "{" delimeters reached.
+  unsigned int state = 0;
+
+  for (; idx < html_buf_size; ++idx) {
+    if ((state & 1) == 0) {
+      // Using 0x7B instead of left curly-brace due to bug in vim navigation.
+      if (html_buf[idx] == 0x7B) {
+        ++delimeter_count;
+        if (delimeter_count >= 3) {
+          delimeter_count = 0;
+          state |= 1;
+          if (template_html_list->count != 0) {
+            C_SIMPLE_HTTP_INTERNAL_Template_Node *last_node =
+              template_html_list->tail->prev->data;
+            last_template_idx = last_node->orig_end_idx;
+          }
+          template_node = malloc(sizeof(C_SIMPLE_HTTP_INTERNAL_Template_Node));
+          template_node->html = malloc(idx - last_template_idx);
+          memcpy(template_node->html, html_buf + idx, idx - last_template_idx);
+          template_node->html_size = idx - last_template_idx;
+          template_node->orig_end_idx = idx + 1;
+          template_node->forced_next = NULL;
+          simple_archiver_list_add(template_html_list, template_node,
+            c_simple_http_internal_free_template_node);
+          template_node = NULL;
+        }
+      } else {
+        delimeter_count = 0;
+      }
+    } else {
+      // (state & 1) is 1
+      // Using 0x7D instead of right curly-brace due to bug in vim navigation.
+      if (html_buf[idx] == 0x7D) {
+        ++delimeter_count;
+        if (delimeter_count >= 3) {
+          delimeter_count = 0;
+          state &= 0xFFFFFFFE;
+          C_SIMPLE_HTTP_INTERNAL_Template_Node *last_node =
+            template_html_list->tail->prev->data;
+          size_t end_of_var_size =
+            idx - last_node->orig_end_idx;
+          if (end_of_var_size <= 6) {
+            fprintf(
+              stderr,
+              "ERROR generating from html template, invalid delimeter at index "
+              "%lu!\n",
+              idx);
+            return NULL;
+          }
+          size_t var_size = end_of_var_size - 6;
+          char *var = malloc(var_size + 1);
+          memcpy(
+            var,
+            html_buf + last_node->orig_end_idx + 3,
+            var_size);
+          var[var_size] = 0;
+          const char *value_c_str =
+            simple_archiver_hash_map_get(
+              wrapped_hash_map->hash_map,
+              var,
+              var_size + 1);
+          // TODO Impl. loading from file instead of directly from value.
+          // Perhaps do this if "var" ends with "_FILE".
+          if (value_c_str) {
+            template_node =
+              malloc(sizeof(C_SIMPLE_HTTP_INTERNAL_Template_Node));
+            size_t size = strlen(value_c_str);
+            template_node->html = malloc(size);
+            memcpy(template_node->html, value_c_str, size);
+            template_node->html_size = size;
+            template_node->orig_end_idx = idx + 1;
+            template_node->forced_next = NULL;
+          } else {
+            template_node =
+              malloc(sizeof(C_SIMPLE_HTTP_INTERNAL_Template_Node));
+            template_node->html = NULL;
+            template_node->html_size = 0;
+            template_node->orig_end_idx = idx + 1;
+            template_node->forced_next = NULL;
+          }
+          simple_archiver_list_add(template_html_list, template_node,
+            c_simple_http_internal_free_template_node);
+          template_node = NULL;
+        }
+      } else {
+        delimeter_count = 0;
+      }
+    }
+  }
+
+  if (template_html_list->count != 0) {
+    C_SIMPLE_HTTP_INTERNAL_Template_Node *last_node =
+      template_html_list->tail->prev->data;
+    if (idx > last_node->orig_end_idx) {
+      template_node = malloc(sizeof(C_SIMPLE_HTTP_INTERNAL_Template_Node));
+      size_t size = idx - last_node->orig_end_idx;
+      template_node->html = malloc(size);
+      memcpy(template_node->html, html_buf + last_node->orig_end_idx, size);
+      template_node->html_size = size;
+      template_node->orig_end_idx = idx + 1;
+      template_node->forced_next = NULL;
+      simple_archiver_list_add(template_html_list, template_node,
+        c_simple_http_internal_free_template_node);
+      template_node = NULL;
+
+      last_node = template_html_list->tail->prev->data;
+    }
+    size_t final_size = 0;
+    simple_archiver_list_get(
+      template_html_list,
+      c_simple_http_internal_get_final_size_fn,
+      &final_size);
+    if (final_size == 0) {
+      fprintf(stderr, "ERROR final_size calculated as ZERO from templates!\n");
+      return NULL;
+    }
+    C_SIMPLE_HTTP_INTERNAL_Template_Node to_fill;
+    to_fill.html = malloc(final_size);
+    to_fill.html_size = 0;
+    to_fill.html_capacity = final_size;
+    if (simple_archiver_list_get(
+        template_html_list,
+        c_simple_http_internal_fill_buf_fn,
+        &to_fill) != NULL) {
+      fprintf(stderr, "ERROR internal issue processing final html buffer!\n");
+      free(to_fill.html);
+      return NULL;
+    }
+    return to_fill.html;
+  } else {
+    // Prevent cleanup fn from "free"ing html_buf and return it verbatim.
+    char *buf = html_buf;
+    html_buf = NULL;
+    return buf;
+  }
+}
+
+// vim: ts=2 sts=2 sw=2

src/http_template.h

@@ -0,0 +1,30 @@
+// ISC License
+// 
+// Copyright (c) 2024 Stephen Seo
+// 
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+#ifndef SEODISPARATE_COM_C_SIMPLE_HTTP_HTTP_TEMPLATE_H_
+#define SEODISPARATE_COM_C_SIMPLE_HTTP_HTTP_TEMPLATE_H_
+
+#include "http.h"
+
+// Returns non-NULL on success, which must be free'd after use.
+// Takes a path string and templates and returns the generated HTML.
+char *c_simple_http_path_to_generated(
+  const char *path,
+  const C_SIMPLE_HTTP_HTTPTemplates *templates);
+
+#endif
+
+// vim: ts=2 sts=2 sw=2