/**************************************************************************** * apps/graphics/traveler/tools/libwld/wld_inifile.c * * Copyright (C) 2016 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include "wld_inifile.h" /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* The maximum size of a line in the INI file */ #define INFILE_MAXLINE 256 /**************************************************************************** * Private Types ****************************************************************************/ /* A structure that describes one entry from the INI file */ struct inifile_var_s { char *variable; char *value; }; /* This structure describes the state of one instance of the INI file parser */ struct inifile_state_s { FILE *instream; int nextch; char line[INFILE_MAXLINE+1]; }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ static bool inifile_next_line(struct inifile_state_s *priv); static int inifile_read_line(struct inifile_state_s *priv); static int inifile_read_noncomment_line(struct inifile_state_s *priv); static bool inifile_seek_to_section(struct inifile_state_s *priv, const char *section); static bool inifile_read_variable(struct inifile_state_s *priv, struct inifile_var_s *varinfo); static char *inifile_find_section_variable(struct inifile_state_s *priv, const char *variable); static char *inifile_find_variable(struct inifile_state_s *priv, const char *section, const char *variable); /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: inifile_next_line * * Description: * Skip to the first character of the next line. Returns true if the end * of file was not encountered. * ****************************************************************************/ static bool inifile_next_line(struct inifile_state_s *priv) { /* Search ahead for the end of line mark (or possibly the end of file mark) */ while ((priv->nextch != '\n') && (priv->nextch != EOF)) { priv->nextch = getc(priv->instream); } /* Re-prime the pump with the first character from the next line. NOTE: * this logic depends on the fact that getc() will return EOF repeatedly. */ priv->nextch = getc(priv->instream); return (priv->nextch != EOF); } /**************************************************************************** * Name: inifile_read_line * * Description: * Read the next line from the INI file into the line buffer and return * the number of characters read into the buffer. If we hit the end of a * section (or the end of a file), this function will return a count of * zero. * ****************************************************************************/ static int inifile_read_line(struct inifile_state_s *priv) { int nbytes; /* Assuming that the file pointer is correctly positioned at the beginning * of the next line, read until the end of line indication is found (or * until the line buffer is full). This is basically fgets(). */ nbytes = 0; while ((nbytes < INFILE_MAXLINE) && (priv->nextch != EOF) && (priv->nextch != '\n')) { /* Always ignore carriage returns */ if (priv->nextch != '\r') { /* Ignore any leading whitespace on the line */ if (nbytes || (priv->nextch != ' ' && priv->nextch != '\t')) { /* Add the new character to the line buffer */ priv->line[nbytes] = priv->nextch; nbytes++; } } /* Get the next character from the INI file */ priv->nextch = getc(priv->instream); } /* NUL terminate the string */ priv->line[nbytes] = '\0'; /* Skip to the first character of the next line. This should normally * just amount to skipping over the newline, but could be more involved * if we had to truncate the line to fit into the line buffer. */ if (priv->nextch != EOF) { (void)inifile_next_line(priv); } /* And return the number of bytes read (excluding the NUL terminator and * leading whitespace). */ return nbytes; } /**************************************************************************** * Name: inifile_read_noncomment_line * * Description: * Read until either a (1) no further lines are found in the file, or (2) * a line that does not begin with a semi-colon is found * ****************************************************************************/ static int inifile_read_noncomment_line(struct inifile_state_s *priv) { int nbytes; /* Read until either a (1) no further lines are found in * the file, or (2) a line that does not begin with a semi-colon * is found. */ do nbytes = inifile_read_line(priv); while (nbytes > 0 && priv->line[0] == ';'); return nbytes; } /**************************************************************************** * Name: inifile_seek_to_section * * Description: * Positions the file pointer to the line containing the first variable * description within the INI file. Returns 1 if the section was found. * In this case, the file pointer will be positioned at the beginning of * the first variable line. * ****************************************************************************/ static bool inifile_seek_to_section(struct inifile_state_s *priv, const char *section) { int nbytes; /* Rewind to the beginning of the INI file and re-prime the pump with the * first character from the INI file. */ rewind(priv->instream); priv->nextch = getc(priv->instream); /* Loop until either the section is found, or until we hit the end of the * INI file. */ do { /* Read the next line into the input buffer. A returned value of zero * bytes means nothing special here -- could be EOF or a blank line. */ nbytes = inifile_read_noncomment_line(priv); /* It takes at least three bytes of data to be a candidate for a * section header. */ if (nbytes >= 3) { /* A section header must begin with a left bracket */ if (priv->line[0] == '[') { /* The section name should start with the first character * after the left bracket. */ char *sectend; /* The section name should extend to the right bracket. */ sectend = strchr(&priv->line[1], ']'); /* Replace the right bracket (if found) with a NULL * terminator. */ if (sectend) { *sectend = '\0'; } /* Then compare the section name to the one we are looking for */ if (strcasecmp(&priv->line[1], section) == 0) { /* The section names match! Return success */ return true; } } } } while (priv->nextch != EOF); /* If we got here, we search the whole INI file without finding * the requested section */ return false; } /**************************************************************************** * Name: inifile_read_variable * * Description: * Obtain variable info from the next line in the section. This assumes * that the file pointer is pointing to the beginning of the next line. * If there is no further data in the section, false is returned. * ****************************************************************************/ static bool inifile_read_variable(struct inifile_state_s *priv, struct inifile_var_s *varinfo) { char *ptr; /* Read until either (1) the end of file is found, (2) the end of * the section is found, or (3) a valid variable assignment is found. */ for (;;) { /* Read the next line in the buffer */ int nbytes = inifile_read_noncomment_line(priv); /* Make sure that the line is non-NULL and that this is not the * beginning of a new section */ if (!nbytes || priv->line[0] == '[') { return false; } /* Search for the '=' delimiter. NOTE the line is guaranteed to * be NULL terminated by inifile_read_noncomment_line(). */ ptr = strchr(&priv->line[1], '='); /* If the delimiter was found, return success */ if (ptr) { /* Put NUL termination between the variable name and the * variable value (replacing the equal sign). */ *ptr = '\0'; /* Set up the return structure. NOTE: value may point at * a NULL string */ varinfo->variable = (char*)priv->line; varinfo->value = (ptr + 1); return true; } } } /**************************************************************************** * Name: inifile_find_section_variable * * Description: * Find the value string associated with the variable name. This function * will return NULL on failure to find the variable. It will return a * pointer to an empty string is the variable is found, but not assigned a * value. * ****************************************************************************/ static char *inifile_find_section_variable(struct inifile_state_s *priv, const char *variable) { /* Loop until either (1) we hit the end of file, (2) we hit the end * of the section, or (3) we find the variable that we are looking * for/ */ for (;;) { /* Get the next variable from this section. */ struct inifile_var_s varinfo; bool found = inifile_read_variable(priv, &varinfo); /* Is there anything left in the section? */ if (!found) { return NULL; } /* Does the variable name match the one we are looking for? */ if (strcasecmp(varinfo.variable, variable) == 0) { /* Yes... then we have it! */ return varinfo.value; } } } /**************************************************************************** * Name: inifile_find_variable * * Description: * Obtains the specified string value for the specified variable name * within the specified section of the INI file. * ****************************************************************************/ static char *inifile_find_variable(struct inifile_state_s *priv, const char *section, const char *variable) { char *ret = NULL; /* Seek to the first variable in the specified section of the INI file */ if (priv->instream && inifile_seek_to_section(priv, section)) { /* If the seek was successful, then find the value string within * the section */ char *value = inifile_find_section_variable(priv, variable); if (value && *value) { ret = value; } } /* Return the string that we found. */ return ret; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: inifile_initialize * * Description: * Initialize for access to the INI file 'inifile_name' * ****************************************************************************/ INIHANDLE inifile_initialize(const char *inifile_name) { /* Allocate an INI file parser state structure */ struct inifile_state_s *priv = (struct inifile_state_s *)malloc(sizeof(struct inifile_state_s)); if (!priv) { return (INIHANDLE)NULL; } /* Open the specified INI file for reading */ priv->instream = fopen(inifile_name, "r"); /* Prime the pump */ if (priv->instream) { priv->nextch = getc(priv->instream); return (INIHANDLE)priv; } else { return (INIHANDLE)NULL; } } /**************************************************************************** * Name: inifile_uninitialize * * Description: * Free resources commit to INI file parsing * ****************************************************************************/ void inifile_uninitialize(INIHANDLE handle) { struct inifile_state_s *priv = (struct inifile_state_s *)handle; if (priv) { /* Close the INI file stream */ if (priv->instream) { fclose(priv->instream); } /* Release the state structure */ free(priv); } } /**************************************************************************** * Name: inifile_read_string * * Description: * Obtains the specified string value for the specified variable name * within the specified section of the INI file. The receiver of the * value string should call inifile_free_string when it no longer needs * the memory held by the value string. * ****************************************************************************/ char *inifile_read_string(INIHANDLE handle, const char *section, const char *variable, const char *defvalue) { struct inifile_state_s *priv = (struct inifile_state_s *)handle; char *ret = NULL; const char *value; /* Get a reference to the volatile version of the string */ value = inifile_find_variable(priv, section, variable); /* If the variable was not found, then use the default value */ if (!value) { /* Selecting the default string */ value = defvalue; } /* If this was successful, create a non-volatile copy of the string * We do this even if the default value is used because the caller * will (eventually) deallocate it. */ if (value) { ret = strdup(value); } /* Return the string that we found. */ return ret; } /**************************************************************************** * Name: inifile_read_integer * * Description: * Obtains the specified integer value for the specified variable name * within the specified section of the INI file * ****************************************************************************/ long inifile_read_integer(INIHANDLE handle, const char *section, const char *variable, long defvalue) { struct inifile_state_s *priv = (struct inifile_state_s *)handle; char *value; long ret = defvalue; /* Get the value as a string first */ value = inifile_find_variable(priv, section, variable); /* If this was successful, then convert the string to an integer value. */ if (value) { /* Then convert the string to an integer value (accept any base, and * ignore all conversion errors. */ ret = strtol(value, NULL, 0); } /* Return the value that we found. */ return ret; } /**************************************************************************** * Name: inifile_free_string * * Description: * Release resources allocated for the value string previously obtained * from inifile_read_string. The purpose of this inline function is to * hide the memory allocator used by this implementation. * ****************************************************************************/ void inifile_free_string(char *value) { if (value) { free(value); } }