/src/php-src/ext/standard/browscap.c

Source (jump to first uncovered line)
/*
   +----------------------------------------------------------------------+
   | Copyright (c) The PHP Group                                          |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | https://www.php.net/license/3_01.txt                                 |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Author: Zeev Suraski <zeev@php.net>                                  |
   +----------------------------------------------------------------------+
 */

#include "php.h"
#include "php_browscap.h"
#include "php_ini.h"

#include "zend_ini_scanner.h"
#include "zend_globals.h"

#define BROWSCAP_NUM_CONTAINS 5

typedef struct {
  zend_string *key;
  zend_string *value;
} browscap_kv;

typedef struct {
  zend_string *pattern;
  zend_string *parent;
  uint32_t kv_start;
  uint32_t kv_end;
  /* We ensure that the length fits in 16 bits, so this is fine */
  uint16_t contains_start[BROWSCAP_NUM_CONTAINS];
  uint8_t contains_len[BROWSCAP_NUM_CONTAINS];
  uint8_t prefix_len;
} browscap_entry;

typedef struct {
  HashTable *htab;
  browscap_kv *kv;
  uint32_t kv_used;
  uint32_t kv_size;
  char filename[MAXPATHLEN];
} browser_data;

/* browser data defined in startup phase, eagerly loaded in MINIT */
static browser_data global_bdata = {0};

/* browser data defined in activation phase, lazily loaded in get_browser.
 * Per request and per thread, if applicable */
ZEND_BEGIN_MODULE_GLOBALS(browscap)
  browser_data activation_bdata;
ZEND_END_MODULE_GLOBALS(browscap)

ZEND_DECLARE_MODULE_GLOBALS(browscap)
#define BROWSCAP_G(v) ZEND_MODULE_GLOBALS_ACCESSOR(browscap, v)

#define DEFAULT_SECTION_NAME "Default Browser Capability Settings"

/* OBJECTS_FIXME: This whole extension needs going through. The use of objects looks pretty broken here */

static void browscap_entry_dtor(zval *zvalue)
{
  browscap_entry *entry = Z_PTR_P(zvalue);
  zend_string_release_ex(entry->pattern, 0);
  if (entry->parent) {
    zend_string_release_ex(entry->parent, 0);
  }
  efree(entry);
}

static void browscap_entry_dtor_persistent(zval *zvalue)
{
  browscap_entry *entry = Z_PTR_P(zvalue);
  zend_string_release_ex(entry->pattern, 1);
  if (entry->parent) {
    zend_string_release_ex(entry->parent, 1);
  }
  pefree(entry, 1);
}

static inline bool is_placeholder(char c) {
  return c == '?' || c == '*';
}

/* Length of prefix not containing any wildcards */
static uint8_t browscap_compute_prefix_len(const zend_string *pattern) {
  size_t i;
  for (i = 0; i < ZSTR_LEN(pattern); i++) {
    if (is_placeholder(ZSTR_VAL(pattern)[i])) {
      break;
    }
  }
  return (uint8_t)MIN(i, UINT8_MAX);
}

static size_t browscap_compute_contains(
    zend_string *pattern, size_t start_pos,
    uint16_t *contains_start, uint8_t *contains_len) {
  size_t i = start_pos;
  /* Find first non-placeholder character after prefix */
  for (; i < ZSTR_LEN(pattern); i++) {
    if (!is_placeholder(ZSTR_VAL(pattern)[i])) {
      /* Skip the case of a single non-placeholder character.
       * Let's try to find something longer instead. */
      if (i + 1 < ZSTR_LEN(pattern) &&
          !is_placeholder(ZSTR_VAL(pattern)[i + 1])) {
        break;
      }
    }
  }
  *contains_start = (uint16_t)i;

  /* Find first placeholder character after that */
  for (; i < ZSTR_LEN(pattern); i++) {
    if (is_placeholder(ZSTR_VAL(pattern)[i])) {
      break;
    }
  }
  *contains_len = (uint8_t)MIN(i - *contains_start, UINT8_MAX);
  return i;
}

/* Length of regex, including escapes, anchors, etc. */
static size_t browscap_compute_regex_len(const zend_string *pattern) {
  size_t i, len = ZSTR_LEN(pattern);
  for (i = 0; i < ZSTR_LEN(pattern); i++) {
    switch (ZSTR_VAL(pattern)[i]) {
      case '*':
      case '.':
      case '\\':
      case '(':
      case ')':
      case '~':
      case '+':
        len++;
        break;
    }
  }

  return len + sizeof("~^$~")-1;
}

static zend_string *browscap_convert_pattern(const zend_string *pattern, bool persistent) /* {{{ */
{
  size_t i, j=0;
  char *t;
  zend_string *res;

  res = zend_string_alloc(browscap_compute_regex_len(pattern), persistent);
  t = ZSTR_VAL(res);

  t[j++] = '~';
  t[j++] = '^';

  for (i = 0; i < ZSTR_LEN(pattern); i++, j++) {
    char c = ZSTR_VAL(pattern)[i];
    switch (c) {
      case '?':
        t[j] = '.';
        break;
      case '*':
        t[j++] = '.';
        t[j] = '*';
        break;
      case '.':
        t[j++] = '\\';
        t[j] = '.';
        break;
      case '\\':
        t[j++] = '\\';
        t[j] = '\\';
        break;
      case '(':
        t[j++] = '\\';
        t[j] = '(';
        break;
      case ')':
        t[j++] = '\\';
        t[j] = ')';
        break;
      case '~':
        t[j++] = '\\';
        t[j] = '~';
        break;
      case '+':
        t[j++] = '\\';
        t[j] = '+';
        break;
      default:
        t[j] = zend_tolower_ascii(c);
        break;
    }
  }

  t[j++] = '$';
  t[j++] = '~';
  t[j]=0;

  ZSTR_LEN(res) = j;
  return res;
}
/* }}} */

typedef struct _browscap_parser_ctx {
  browser_data *bdata;
  browscap_entry *current_entry;
  zend_string *current_section_name;
  HashTable str_interned;
} browscap_parser_ctx;

static zend_string *browscap_intern_str(
    browscap_parser_ctx *ctx, zend_string *str, bool persistent) {
  zend_string *interned = zend_hash_find_ptr(&ctx->str_interned, str);
  if (interned) {
    zend_string_addref(interned);
  } else {
    interned = zend_string_copy(str);
    if (persistent) {
      interned = zend_new_interned_string(interned);
    }
    zend_hash_add_new_ptr(&ctx->str_interned, interned, interned);
  }

  return interned;
}

static zend_string *browscap_intern_str_ci(
    browscap_parser_ctx *ctx, zend_string *str, bool persistent) {
  zend_string *lcname;
  zend_string *interned;
  ALLOCA_FLAG(use_heap);

  ZSTR_ALLOCA_ALLOC(lcname, ZSTR_LEN(str), use_heap);
  zend_str_tolower_copy(ZSTR_VAL(lcname), ZSTR_VAL(str), ZSTR_LEN(str));
  interned = zend_hash_find_ptr(&ctx->str_interned, lcname);

  if (interned) {
    zend_string_addref(interned);
  } else {
    interned = zend_string_init(ZSTR_VAL(lcname), ZSTR_LEN(lcname), persistent);
    if (persistent) {
      interned = zend_new_interned_string(interned);
    }
    zend_hash_add_new_ptr(&ctx->str_interned, interned, interned);
  }

  ZSTR_ALLOCA_FREE(lcname, use_heap);
  return interned;
}

static void browscap_add_kv(
    browser_data *bdata, zend_string *key, zend_string *value, bool persistent) {
  if (bdata->kv_used == bdata->kv_size) {
    bdata->kv_size *= 2;
    bdata->kv = safe_perealloc(bdata->kv, sizeof(browscap_kv), bdata->kv_size, 0, persistent);
  }

  bdata->kv[bdata->kv_used].key = key;
  bdata->kv[bdata->kv_used].value = value;
  bdata->kv_used++;
}

static void browscap_entry_add_kv_to_existing_array(browser_data *bdata, browscap_entry *entry, HashTable *ht) {
  for (uint32_t i = entry->kv_start; i < entry->kv_end; i++) {
    zval tmp;
    ZVAL_STR_COPY(&tmp, bdata->kv[i].value);
    zend_hash_add(ht, bdata->kv[i].key, &tmp);
  }
}

static HashTable *browscap_entry_to_array(browser_data *bdata, browscap_entry *entry) {
  zval tmp;
  HashTable *ht = zend_new_array(2 + (entry->parent ? 1 : 0) + (entry->kv_end - entry->kv_start));

  ZVAL_STR(&tmp, browscap_convert_pattern(entry->pattern, 0));
  zend_string *key = ZSTR_INIT_LITERAL("browser_name_regex", 0);
  ZSTR_H(key) = zend_inline_hash_func("browser_name_regex", sizeof("browser_name_regex")-1);
  zend_hash_add_new(ht, key, &tmp);
  zend_string_release_ex(key, false);

  ZVAL_STR_COPY(&tmp, entry->pattern);
  key = ZSTR_INIT_LITERAL("browser_name_pattern", 0);
  ZSTR_H(key) = zend_inline_hash_func("browser_name_pattern", sizeof("browser_name_pattern")-1);
  zend_hash_add_new(ht, key, &tmp);
  zend_string_release_ex(key, false);

  if (entry->parent) {
    ZVAL_STR_COPY(&tmp, entry->parent);
    zend_hash_add_new(ht, ZSTR_KNOWN(ZEND_STR_PARENT), &tmp);
  }

  browscap_entry_add_kv_to_existing_array(bdata, entry, ht);

  return ht;
}

static void php_browscap_parser_cb(zval *arg1, zval *arg2, zval *arg3, int callback_type, void *arg) /* {{{ */
{
  browscap_parser_ctx *ctx = arg;
  browser_data *bdata = ctx->bdata;
  bool persistent = GC_FLAGS(bdata->htab) & IS_ARRAY_PERSISTENT;

  if (!arg1) {
    return;
  }

  switch (callback_type) {
    case ZEND_INI_PARSER_ENTRY:
      if (ctx->current_entry != NULL && arg2) {
        zend_string *new_value;

        /* Set proper value for true/false settings */
        if (zend_string_equals_literal_ci(Z_STR_P(arg2), "on")
          || zend_string_equals_literal_ci(Z_STR_P(arg2), "yes")
          || zend_string_equals_literal_ci(Z_STR_P(arg2), "true")
        ) {
          new_value = ZSTR_CHAR('1');
        } else if (zend_string_equals_literal_ci(Z_STR_P(arg2), "no")
          || zend_string_equals_literal_ci(Z_STR_P(arg2), "off")
          || zend_string_equals_literal_ci(Z_STR_P(arg2), "none")
          || zend_string_equals_literal_ci(Z_STR_P(arg2), "false")
        ) {
          new_value = ZSTR_EMPTY_ALLOC();
        } else { /* Other than true/false setting */
          new_value = browscap_intern_str(ctx, Z_STR_P(arg2), persistent);
        }

        if (zend_string_equals_ci(Z_STR_P(arg1), ZSTR_KNOWN(ZEND_STR_PARENT))) {
          /* parent entry cannot be same as current section -> causes infinite loop! */
          if (ctx->current_section_name != NULL &&
            zend_string_equals_ci(ctx->current_section_name, Z_STR_P(arg2))
          ) {
            zend_error(E_CORE_ERROR, "Invalid browscap ini file: "
              "'Parent' value cannot be same as the section name: %s "
              "(in file %s)", ZSTR_VAL(ctx->current_section_name), INI_STR("browscap"));
            return;
          }

          if (ctx->current_entry->parent) {
            zend_string_release(ctx->current_entry->parent);
          }

          ctx->current_entry->parent = new_value;
        } else {
          zend_string *new_key = browscap_intern_str_ci(ctx, Z_STR_P(arg1), persistent);
          browscap_add_kv(bdata, new_key, new_value, persistent);
          ctx->current_entry->kv_end = bdata->kv_used;
        }
      }
      break;
    case ZEND_INI_PARSER_SECTION:
    {
      browscap_entry *entry;
      zend_string *pattern = Z_STR_P(arg1);
      size_t pos;
      int i;

      if (ZSTR_LEN(pattern) > UINT16_MAX) {
        php_error_docref(NULL, E_WARNING,
          "Skipping excessively long pattern of length %zd", ZSTR_LEN(pattern));
        break;
      }

      if (persistent) {
        pattern = zend_new_interned_string(zend_string_copy(pattern));
        if (ZSTR_IS_INTERNED(pattern)) {
          Z_TYPE_FLAGS_P(arg1) = 0;
        } else {
          zend_string_release(pattern);
        }
      }

      entry = ctx->current_entry
        = pemalloc(sizeof(browscap_entry), persistent);
      zend_hash_update_ptr(bdata->htab, pattern, entry);

      if (ctx->current_section_name) {
        zend_string_release(ctx->current_section_name);
      }
      ctx->current_section_name = zend_string_copy(pattern);

      entry->pattern = zend_string_copy(pattern);
      entry->kv_end = entry->kv_start = bdata->kv_used;
      entry->parent = NULL;

      pos = entry->prefix_len = browscap_compute_prefix_len(pattern);
      for (i = 0; i < BROWSCAP_NUM_CONTAINS; i++) {
        pos = browscap_compute_contains(pattern, pos,
          &entry->contains_start[i], &entry->contains_len[i]);
      }
      break;
    }
  }
}
/* }}} */

static zend_result browscap_read_file(char *filename, browser_data *browdata, bool persistent) /* {{{ */
{
  zend_file_handle fh;
  browscap_parser_ctx ctx = {0};
  FILE *fp;

  if (filename == NULL || filename[0] == '\0') {
    return FAILURE;
  }

  fp = VCWD_FOPEN(filename, "r");
  if (!fp) {
    zend_error(E_CORE_WARNING, "Cannot open \"%s\" for reading", filename);
    return FAILURE;
  }
  zend_stream_init_fp(&fh, fp, filename);

  browdata->htab = pemalloc(sizeof *browdata->htab, persistent);
  zend_hash_init(browdata->htab, 0, NULL,
    persistent ? browscap_entry_dtor_persistent : browscap_entry_dtor, persistent);

  browdata->kv_size = 16 * 1024;
  browdata->kv_used = 0;
  browdata->kv = pemalloc(sizeof(browscap_kv) * browdata->kv_size, persistent);

  /* Create parser context */
  ctx.bdata = browdata;
  ctx.current_entry = NULL;
  ctx.current_section_name = NULL;
  /* No dtor because we don't inc the refcount for the reference stored within the hash table's entry value
   * as the hash table is only temporary anyway. */
  zend_hash_init(&ctx.str_interned, 8, NULL, NULL, persistent);

  zend_parse_ini_file(&fh, persistent, ZEND_INI_SCANNER_RAW,
      (zend_ini_parser_cb_t) php_browscap_parser_cb, &ctx);

  /* Destroy parser context */
  if (ctx.current_section_name) {
    zend_string_release(ctx.current_section_name);
  }
  zend_hash_destroy(&ctx.str_interned);
  zend_destroy_file_handle(&fh);

  return SUCCESS;
}
/* }}} */

#ifdef ZTS
static void browscap_globals_ctor(zend_browscap_globals *browscap_globals) /* {{{ */
{
  browscap_globals->activation_bdata.htab = NULL;
  browscap_globals->activation_bdata.kv = NULL;
  browscap_globals->activation_bdata.filename[0] = '\0';
}
/* }}} */
#endif

static void browscap_bdata_dtor(browser_data *bdata, bool persistent) /* {{{ */
{
  if (bdata->htab != NULL) {
    uint32_t i;

    zend_hash_destroy(bdata->htab);
    pefree(bdata->htab, persistent);
    bdata->htab = NULL;

    for (i = 0; i < bdata->kv_used; i++) {
      zend_string_release(bdata->kv[i].key);
      zend_string_release(bdata->kv[i].value);
    }
    pefree(bdata->kv, persistent);
    bdata->kv = NULL;
  }
  bdata->filename[0] = '\0';
}
/* }}} */

/* {{{ PHP_INI_MH */
PHP_INI_MH(OnChangeBrowscap)
{
  if (stage == PHP_INI_STAGE_STARTUP) {
    /* value handled in browscap.c's MINIT */
    return SUCCESS;
  } else if (stage == PHP_INI_STAGE_ACTIVATE) {
    browser_data *bdata = &BROWSCAP_G(activation_bdata);
    if (bdata->filename[0] != '\0') {
      browscap_bdata_dtor(bdata, 0);
    }
    if (VCWD_REALPATH(ZSTR_VAL(new_value), bdata->filename) == NULL) {
      return FAILURE;
    }
    return SUCCESS;
  }

  return FAILURE;
}
/* }}} */

PHP_MINIT_FUNCTION(browscap) /* {{{ */
{
  char *browscap = INI_STR("browscap");

#ifdef ZTS
  ts_allocate_id(&browscap_globals_id, sizeof(browser_data), (ts_allocate_ctor) browscap_globals_ctor, NULL);
#endif
  /* ctor call not really needed for non-ZTS */

  if (browscap && browscap[0]) {
    if (browscap_read_file(browscap, &global_bdata, true) == FAILURE) {
      return FAILURE;
    }
  }

  return SUCCESS;
}
/* }}} */

PHP_RSHUTDOWN_FUNCTION(browscap) /* {{{ */
{
  browser_data *bdata = &BROWSCAP_G(activation_bdata);
  if (bdata->filename[0] != '\0') {
    browscap_bdata_dtor(bdata, 0);
  }

  return SUCCESS;
}
/* }}} */

PHP_MSHUTDOWN_FUNCTION(browscap) /* {{{ */
{
  browscap_bdata_dtor(&global_bdata, 1);

  return SUCCESS;
}
/* }}} */

static inline size_t browscap_get_minimum_length(const browscap_entry *entry) {
  size_t len = entry->prefix_len;
  int i;
  for (i = 0; i < BROWSCAP_NUM_CONTAINS; i++) {
    len += entry->contains_len[i];
  }
  return len;
}

static bool browscap_match_string_wildcard(const char *s, const char *s_end, const char *pattern, const char *pattern_end)
{
  const char *pattern_current = pattern;
  const char *s_current = s;

  const char *wildcard_pattern_restore_pos = NULL;
  const char *wildcard_s_restore_pos = NULL;

  while (s_current < s_end) {
    char pattern_char = *pattern_current;
    char s_char = *s_current;

    if (pattern_char == '*') {
      /* Collapse wildcards */
      pattern_current++;
      while (pattern_current < pattern_end && *pattern_current == '*') {
        pattern_current++;
      }

      /* If we're at the end of the pattern, it means that the ending was just '*', so this is a trivial match */
      if (pattern_current == pattern_end) {
        return true;
      }

      /* Optimization: if there is a non-wildcard character X after a *, then we can immediately jump to the first
       * character X in s starting from s_current because it is the only way to match beyond the *. */
      if (*pattern_current != '?') {
        while (s_current < s_end && *s_current != *pattern_current) {
          s_current++;
        }
      }

      /* We will first assume the skipped part by * is a 0-length string (or n-length if the optimization above skipped n characters).
       * When a mismatch happens we will backtrack and move s one position to assume * skipped a 1-length string.
       * Then 2, 3, 4, ... */
      wildcard_pattern_restore_pos = pattern_current;
      wildcard_s_restore_pos = s_current;

      continue;
    } else if (pattern_char == s_char || pattern_char == '?') {
      /* Match */
      pattern_current++;
      s_current++;

      /* If this was the last character of the pattern, we either fully matched s, or we have a mismatch */
      if (pattern_current == pattern_end) {
        if (s_current == s_end) {
          return true;
        }
        /* Fallthrough to mismatch */
      } else {
        continue;
      }
    }

    /* Mismatch */
    if (wildcard_pattern_restore_pos) {
      pattern_current = wildcard_pattern_restore_pos;
      wildcard_s_restore_pos++;
      s_current = wildcard_s_restore_pos;
    } else {
      /* No wildcard is active, so it is impossible to match */
      return false;
    }
  }

  /* Skip remaining * wildcards, they match nothing here as we are at the end of s */
  while (pattern_current < pattern_end && *pattern_current == '*') {
    pattern_current++;
  }

  ZEND_ASSERT(s_current == s_end);
  return pattern_current == pattern_end;
}

static int browser_reg_compare(browscap_entry *entry, const zend_string *agent_name, browscap_entry **found_entry_ptr, size_t *cached_prev_len) /* {{{ */
{
  browscap_entry *found_entry = *found_entry_ptr;
  ALLOCA_FLAG(use_heap)
  zend_string *pattern_lc;
  const char *cur;

  /* Lowercase the pattern, the agent name is already lowercase */
  ZSTR_ALLOCA_ALLOC(pattern_lc, ZSTR_LEN(entry->pattern), use_heap);
  zend_str_tolower_copy(ZSTR_VAL(pattern_lc), ZSTR_VAL(entry->pattern), ZSTR_LEN(entry->pattern));

  /* Check if the agent contains the "contains" portions */
  cur = ZSTR_VAL(agent_name) + entry->prefix_len;
  for (int i = 0; i < BROWSCAP_NUM_CONTAINS; i++) {
    if (entry->contains_len[i] != 0) {
      cur = zend_memnstr(cur,
        ZSTR_VAL(pattern_lc) + entry->contains_start[i],
        entry->contains_len[i],
        ZSTR_VAL(agent_name) + ZSTR_LEN(agent_name));
      if (!cur) {
        ZSTR_ALLOCA_FREE(pattern_lc, use_heap);
        return 0;
      }
      cur += entry->contains_len[i];
    }
  }

  /* See if we have an exact match, if so, we're done... */
  if (zend_string_equals(agent_name, pattern_lc)) {
    *found_entry_ptr = entry;
    /* cached_prev_len doesn't matter here because we end the search when an exact match is found. */
    ZSTR_ALLOCA_FREE(pattern_lc, use_heap);
    return 1;
  }

  if (browscap_match_string_wildcard(
    ZSTR_VAL(agent_name) + entry->prefix_len,
    ZSTR_VAL(agent_name) + ZSTR_LEN(agent_name),
    ZSTR_VAL(pattern_lc) + entry->prefix_len,
    ZSTR_VAL(pattern_lc) + ZSTR_LEN(pattern_lc)
  )) {
    /* If we've found a possible browser, we need to do a comparison of the
       number of characters changed in the user agent being checked versus
       the previous match found and the current match. */
    size_t curr_len = entry->prefix_len; /* Start from the prefix because the prefix is free of wildcards */
    const zend_string *current_match = entry->pattern;
    for (size_t i = curr_len; i < ZSTR_LEN(current_match); i++) {
      switch (ZSTR_VAL(current_match)[i]) {
        case '?':
        case '*':
          /* do nothing, ignore these characters in the count */
        break;

        default:
          ++curr_len;
      }
    }

    if (found_entry) {
      /* Pick which browser pattern replaces the least amount of
         characters when compared to the original user agent string... */
      if (*cached_prev_len < curr_len) {
        *found_entry_ptr = entry;
        *cached_prev_len = curr_len;
      }
    } else {
      *found_entry_ptr = entry;
      *cached_prev_len = curr_len;
    }
  }

  ZSTR_ALLOCA_FREE(pattern_lc, use_heap);
  return 0;
}
/* }}} */

/* {{{ Get information about the capabilities of a browser. If browser_name is omitted or null, HTTP_USER_AGENT is used. Returns an object by default; if return_array is true, returns an array. */
PHP_FUNCTION(get_browser)
{
  zend_string *agent_name = NULL, *lookup_browser_name;
  bool return_array = 0;
  browser_data *bdata;
  browscap_entry *found_entry = NULL;
  HashTable *agent_ht;

  ZEND_PARSE_PARAMETERS_START(0, 2)
    Z_PARAM_OPTIONAL
    Z_PARAM_STR_OR_NULL(agent_name)
    Z_PARAM_BOOL(return_array)
  ZEND_PARSE_PARAMETERS_END();

  if (BROWSCAP_G(activation_bdata).filename[0] != '\0') {
    bdata = &BROWSCAP_G(activation_bdata);
    if (bdata->htab == NULL) { /* not initialized yet */
      if (browscap_read_file(bdata->filename, bdata, false) == FAILURE) {
        RETURN_FALSE;
      }
    }
  } else {
    if (!global_bdata.htab) {
      php_error_docref(NULL, E_WARNING, "browscap ini directive not set");
      RETURN_FALSE;
    }
    bdata = &global_bdata;
  }

  if (agent_name == NULL) {
    zval *http_user_agent = NULL;
    if (Z_TYPE(PG(http_globals)[TRACK_VARS_SERVER]) == IS_ARRAY
        || zend_is_auto_global(ZSTR_KNOWN(ZEND_STR_AUTOGLOBAL_SERVER))) {
      http_user_agent = zend_hash_str_find(
        Z_ARRVAL_P(&PG(http_globals)[TRACK_VARS_SERVER]),
        "HTTP_USER_AGENT", sizeof("HTTP_USER_AGENT")-1);
    }
    if (http_user_agent == NULL) {
      php_error_docref(NULL, E_WARNING, "HTTP_USER_AGENT variable is not set, cannot determine user agent name");
      RETURN_FALSE;
    }
    agent_name = Z_STR_P(http_user_agent);
  }

  lookup_browser_name = zend_string_tolower(agent_name);
  found_entry = zend_hash_find_ptr(bdata->htab, lookup_browser_name);
  if (found_entry == NULL) {
    browscap_entry *entry;
    size_t cached_prev_len = 0; /* silence compiler warning */

    ZEND_HASH_MAP_FOREACH_PTR(bdata->htab, entry) {
      /* The following two early-skip checks are inside this loop instead of inside browser_reg_compare().
       * That's because we want to avoid the call frame overhead, especially as browser_reg_compare() is
       * a function that uses alloca(). */

      /* Agent name too short */
      if (ZSTR_LEN(lookup_browser_name) < browscap_get_minimum_length(entry)) {
        continue;
      }

      /* Quickly discard patterns where the prefix doesn't match. */
      bool prefix_matches = true;
      for (size_t i = 0; i < entry->prefix_len; i++) {
        if (ZSTR_VAL(lookup_browser_name)[i] != zend_tolower_ascii(ZSTR_VAL(entry->pattern)[i])) {
          prefix_matches = false;
          break;
        }
      }
      if (!prefix_matches) {
        continue;
      }

      if (browser_reg_compare(entry, lookup_browser_name, &found_entry, &cached_prev_len)) {
        break;
      }
    } ZEND_HASH_FOREACH_END();

    if (found_entry == NULL) {
      found_entry = zend_hash_str_find_ptr(bdata->htab,
        DEFAULT_SECTION_NAME, sizeof(DEFAULT_SECTION_NAME)-1);
      if (found_entry == NULL) {
        zend_string_release_ex(lookup_browser_name, false);
        RETURN_FALSE;
      }
    }
  }

  zend_string_release_ex(lookup_browser_name, false);

  agent_ht = browscap_entry_to_array(bdata, found_entry);

  if (return_array) {
    RETVAL_ARR(agent_ht);
  } else {
    object_and_properties_init(return_value, zend_standard_class_def, agent_ht);
  }

  HashTable *target_ht = return_array ? Z_ARRVAL_P(return_value) : Z_OBJPROP_P(return_value);

  while (found_entry->parent) {
    found_entry = zend_hash_find_ptr(bdata->htab, found_entry->parent);
    if (found_entry == NULL) {
      break;
    }

    browscap_entry_add_kv_to_existing_array(bdata, found_entry, target_ht);
  }
}
/* }}} */

Coverage Report

Created: 2025-06-13 06:43