moved CGI and IO into separate files

build/Makefile

@@ -29,7 +29,8 @@ VERSION = $(shell perl -lne \
 SOURCES = src/internal.h src/util.c src/string.c src/parse_date.c \
           src/options.c src/crypto.c src/auth.c src/win32.c src/unix.c \
           src/mg_printf.c src/ssl.c src/http_client.c src/mime.c \
-          src/directory.c src/log.c src/mongoose.c src/lua.c
+          src/directory.c src/log.c src/parse_http.c src/io.c src/cgi.c \
+          src/mongoose.c src/lua.c
 
 TINY_SOURCES = ../mongoose.c main.c
 LUA_SOURCES = $(TINY_SOURCES) sqlite3.c lsqlite3.c lua_5.2.1.c

build/src/directory.c

@@ -236,3 +236,36 @@ static void handle_directory_request(struct mg_connection *conn,
   conn->status_code = 200;
 }
 
+// For a given PUT path, create all intermediate subdirectories
+// for given path. Return 0 if the path itself is a directory,
+// or -1 on error, 1 if OK.
+static int put_dir(const char *path) {
+  char buf[PATH_MAX];
+  const char *s, *p;
+  struct file file = STRUCT_FILE_INITIALIZER;
+  int len, res = 1;
+
+  for (s = p = path + 2; (p = strchr(s, '/')) != NULL; s = ++p) {
+    len = p - path;
+    if (len >= (int) sizeof(buf)) {
+      res = -1;
+      break;
+    }
+    memcpy(buf, path, len);
+    buf[len] = '\0';
+
+    // Try to create intermediate directory
+    DEBUG_TRACE(("mkdir(%s)", buf));
+    if (!mg_stat(buf, &file) && mg_mkdir(buf, 0755) != 0) {
+      res = -1;
+      break;
+    }
+
+    // Is path itself a directory?
+    if (p[1] == '\0') {
+      res = 0;
+    }
+  }
+
+  return res;
+}

build/src/io.c

+#include "internal.h"
+
+// Return number of bytes left to read for this connection
+static int64_t left_to_read(const struct mg_connection *conn) {
+  return conn->content_len + conn->request_len - conn->num_bytes_read;
+}
+
+// Write data to the IO channel - opened file descriptor, socket or SSL
+// descriptor. Return number of bytes written.
+static int64_t push(FILE *fp, SOCKET sock, SSL *ssl, const char *buf,
+                    int64_t len) {
+  int64_t sent;
+  int n, k;
+
+  (void) ssl;  // Get rid of warning
+  sent = 0;
+  while (sent < len) {
+
+    // How many bytes we send in this iteration
+    k = len - sent > INT_MAX ? INT_MAX : (int) (len - sent);
+
+#if !defined(NO_SSL)
+    if (ssl != NULL) {
+      n = SSL_write(ssl, buf + sent, k);
+    } else
+#endif
+    if (fp != NULL) {
+      n = (int) fwrite(buf + sent, 1, (size_t) k, fp);
+      if (ferror(fp))
+        n = -1;
+    } else {
+      n = send(sock, buf + sent, (size_t) k, MSG_NOSIGNAL);
+    }
+
+    if (n <= 0)
+      break;
+
+    sent += n;
+  }
+
+  return sent;
+}
+
+// Read from IO channel - opened file descriptor, socket, or SSL descriptor.
+// Return negative value on error, or number of bytes read on success.
+static int pull(FILE *fp, struct mg_connection *conn, char *buf, int len) {
+  int nread;
+
+  if (len <= 0) return 0;
+  if (fp != NULL) {
+    // Use read() instead of fread(), because if we're reading from the CGI
+    // pipe, fread() may block until IO buffer is filled up. We cannot afford
+    // to block and must pass all read bytes immediately to the client.
+    nread = read(fileno(fp), buf, (size_t) len);
+#ifndef NO_SSL
+  } else if (conn->ssl != NULL) {
+    nread = SSL_read(conn->ssl, buf, len);
+#endif
+  } else {
+    nread = recv(conn->client.sock, buf, (size_t) len, 0);
+  }
+  if (nread > 0) {
+    conn->num_bytes_read += nread;
+  }
+
+  return conn->ctx->stop_flag ? -1 : nread;
+}
+
+static int pull_all(FILE *fp, struct mg_connection *conn, char *buf, int len) {
+  int n, nread = 0;
+
+  while (len > 0 && conn->ctx->stop_flag == 0) {
+    n = pull(fp, conn, buf + nread, len);
+    if (n < 0) {
+      nread = n;  // Propagate the error
+      break;
+    } else if (n == 0) {
+      break;  // No more data to read
+    } else {
+      nread += n;
+      len -= n;
+    }
+  }
+
+  return nread;
+}
+
+int mg_read(struct mg_connection *conn, void *buf, int len) {
+  int n, buffered_len, nread = 0;
+  int64_t left;
+
+  if (conn->content_len <= 0) {
+    return 0;
+  }
+
+  // conn->buf           body
+  //    |=================|==========|===============|
+  //    |<--request_len-->|                          |
+  //    |<-----------data_len------->|      conn->buf + conn->buf_size
+
+  // First, check for data buffered in conn->buf by read_request().
+  if (len > 0 && (buffered_len = conn->data_len - conn->request_len) > 0) {
+    char *body = conn->buf + conn->request_len;
+    if (buffered_len > len) buffered_len = len;
+    if (buffered_len > conn->content_len) buffered_len = (int)conn->content_len;
+
+    memcpy(buf, body, (size_t) buffered_len);
+    memmove(body, body + buffered_len,
+            &conn->buf[conn->data_len] - &body[buffered_len]);
+    len -= buffered_len;
+    conn->data_len -= buffered_len;
+    nread += buffered_len;
+  }
+
+  // Read data from the socket.
+  if (len > 0 && (left = left_to_read(conn)) > 0) {
+    if (left < len) {
+      len = (int) left;
+    }
+    n = pull_all(NULL, conn, (char *) buf + nread, (int) len);
+    nread = n >= 0 ? nread + n : n;
+  }
+
+  return nread;
+}
+
+int mg_write(struct mg_connection *conn, const void *buf, int len) {
+  return push(NULL, conn->client.sock, conn->ssl, (const char *) buf,
+                 (int64_t) len);
+}
+
+// Keep reading the input (either opened file descriptor fd, or socket sock,
+// or SSL descriptor ssl) into buffer buf, until \r\n\r\n appears in the
+// buffer (which marks the end of HTTP request). Buffer buf may already
+// have some data. The length of the data is stored in nread.
+// Upon every read operation, increase nread by the number of bytes read.
+static int read_request(FILE *fp, struct mg_connection *conn,
+                        char *buf, int bufsiz, int *nread) {
+  int request_len, n = 0;
+
+  request_len = get_request_len(buf, *nread);
+  while (conn->ctx->stop_flag == 0 &&
+         *nread < bufsiz &&
+         request_len == 0 &&
+         (n = pull(fp, conn, buf + *nread, bufsiz - *nread)) > 0) {
+    *nread += n;
+    assert(*nread <= bufsiz);
+    request_len = get_request_len(buf, *nread);
+  }
+
+  return request_len <= 0 && n <= 0 ? -1 : request_len;
+}
+
+// Send len bytes from the opened file to the client.
+static void send_file_data(struct mg_connection *conn, FILE *fp,
+                           int64_t offset, int64_t len) {
+  char buf[MG_BUF_LEN];
+  int num_read, num_written, to_read;
+
+  // If offset is beyond file boundaries, don't send anything
+  if (offset > 0 && fseeko(fp, offset, SEEK_SET) != 0) {
+    return;
+  }
+
+  while (len > 0) {
+    // Calculate how much to read from the file in the buffer
+    to_read = sizeof(buf);
+    if ((int64_t) to_read > len) {
+      to_read = (int) len;
+    }
+
+    // Read from file, exit the loop on error
+    if ((num_read = fread(buf, 1, (size_t) to_read, fp)) <= 0) {
+      break;
+    }
+
+    // Send read bytes to the client, exit the loop on error
+    if ((num_written = mg_write(conn, buf, (size_t) num_read)) != num_read) {
+      break;
+    }
+
+    // Both read and were successful, adjust counters
+    conn->num_bytes_sent += num_written;
+    len -= num_written;
+  }
+}
+

build/src/parse_http.c

+#include "internal.h"
+
+// Parse HTTP headers from the given buffer, advance buffer to the point
+// where parsing stopped.
+static void parse_http_headers(char **buf, struct mg_request_info *ri) {
+  int i;
+
+  for (i = 0; i < (int) ARRAY_SIZE(ri->http_headers); i++) {
+    ri->http_headers[i].name = skip_quoted(buf, ":", " ", 0);
+    ri->http_headers[i].value = skip(buf, "\r\n");
+    if (ri->http_headers[i].name[0] == '\0')
+      break;
+    ri->num_headers = i + 1;
+  }
+}
+
+static int is_valid_http_method(const char *method) {
+  return !strcmp(method, "GET") || !strcmp(method, "POST") ||
+    !strcmp(method, "HEAD") || !strcmp(method, "CONNECT") ||
+    !strcmp(method, "PUT") || !strcmp(method, "DELETE") ||
+    !strcmp(method, "OPTIONS") || !strcmp(method, "PROPFIND")
+    || !strcmp(method, "MKCOL");
+}
+
+// Parse HTTP request, fill in mg_request_info structure.
+// This function modifies the buffer by NUL-terminating
+// HTTP request components, header names and header values.
+static int parse_http_message(char *buf, int len, struct mg_request_info *ri) {
+  int is_request, request_length = get_request_len(buf, len);
+  if (request_length > 0) {
+    // Reset attributes. DO NOT TOUCH is_ssl, remote_ip, remote_port
+    ri->remote_user = ri->request_method = ri->uri = ri->http_version = NULL;
+    ri->num_headers = 0;
+
+    buf[request_length - 1] = '\0';
+
+    // RFC says that all initial whitespaces should be ingored
+    while (*buf != '\0' && isspace(* (unsigned char *) buf)) {
+      buf++;
+    }
+    ri->request_method = skip(&buf, " ");
+    ri->uri = skip(&buf, " ");
+    ri->http_version = skip(&buf, "\r\n");
+
+    // HTTP message could be either HTTP request or HTTP response, e.g.
+    // "GET / HTTP/1.0 ...." or  "HTTP/1.0 200 OK ..."
+    is_request = is_valid_http_method(ri->request_method);
+    if ((is_request && memcmp(ri->http_version, "HTTP/", 5) != 0) ||
+        (!is_request && memcmp(ri->request_method, "HTTP/", 5) != 0)) {
+      request_length = -1;
+    } else {
+      if (is_request) {
+        ri->http_version += 5;
+      }
+      parse_http_headers(&buf, ri);
+    }
+  }
+  return request_length;
+}
+
+static int parse_range_header(const char *header, int64_t *a, int64_t *b) {
+  return sscanf(header, "bytes=%" INT64_FMT "-%" INT64_FMT, a, b);
+}

build/src/string.c

@@ -374,3 +374,50 @@ int mg_get_cookie(const char *cookie_header, const char *var_name,
   }
   return len;
 }
+
+int mg_get_var(const char *data, size_t data_len, const char *name,
+               char *dst, size_t dst_len) {
+  const char *p, *e, *s;
+  size_t name_len;
+  int len;
+
+  if (dst == NULL || dst_len == 0) {
+    len = -2;
+  } else if (data == NULL || name == NULL || data_len == 0) {
+    len = -1;
+    dst[0] = '\0';
+  } else {
+    name_len = strlen(name);
+    e = data + data_len;
+    len = -1;
+    dst[0] = '\0';
+
+    // data is "var1=val1&var2=val2...". Find variable first
+    for (p = data; p + name_len < e; p++) {
+      if ((p == data || p[-1] == '&') && p[name_len] == '=' &&
+          !mg_strncasecmp(name, p, name_len)) {
+
+        // Point p to variable value
+        p += name_len + 1;
+
+        // Point s to the end of the value
+        s = (const char *) memchr(p, '&', (size_t)(e - p));
+        if (s == NULL) {
+          s = e;
+        }
+        assert(s >= p);
+
+        // Decode variable into destination buffer
+        len = mg_url_decode(p, (size_t)(s - p), dst, dst_len, 1);
+
+        // Redirect error code from -1 to -2 (destination buffer too small).
+        if (len == -1) {
+          len = -2;
+        }
+        break;
+      }
+    }
+  }
+
+  return len;
+}